Secondary II Algebraic Operations Teacher Edition Unit 4 Northern Utah Curriculum Consortium Project Leader Sheri Heiter Weber School District Project Contributors Ashley Martin Bonita Richins Craig Ashton Davis School District Cache School District Cache School District Gerald Jackman Jeff Rawlins Jeremy Young Box Elder School District Box Elder School District Box Elder School District Kip Motta Marie Fitzgerald Mike Hansen Rich School District Cache School District Cache School District Robert Hoggan Sheena Knight Teresa Billings Cache School District Weber School District Weber School District Wendy Barney Helen Heiner Susan Summerkorn Weber School District Davis School District Davis School District Lead Editor Allen Jacobson Davis School District Technical Writer/Editor Dianne Cummins Davis School District NUCC | Secondary II Math i Table of Contents 4.1 STRUCTURE OF EXPRESSIONS .........................................................................................................1 Teacher Notes ..................................................................................................................................................1 Triple Match.................................................................................................................................................1 Assignment: Ready, Set ...............................................................................................................................3 Classroom Activity: Go! ..............................................................................................................................4 Expressions 1 Bell Quiz and Answers .........................................................................................................4 Mathematics Content .......................................................................................................................................5 Triple Match.....................................................................................................................................................6 Ready, Set ........................................................................................................................................................7 Go! ...................................................................................................................................................................9 Expressions 1 Bell Quiz .................................................................................................................................11 4.2 OPERATIONS WITH POLYNOMIALS ..............................................................................................12 Teacher Notes ................................................................................................................................................12 Building Polynomial Functions Activity ...................................................................................................12 Assignment Ready, Set (Operations with Polynomials Worksheet) ..........................................................14 Assignment Go! (Use either option) ..........................................................................................................15 Option 1: Polynomial Puzzles Task ...........................................................................................................15 Option 2: Pascal’s Triangle Task ...............................................................................................................16 Polynomial Bell Quiz 1 ..............................................................................................................................16 Polynomial Bell Quiz 2 ..............................................................................................................................17 Polynomial Bell Quiz 3 ..............................................................................................................................17 Mathematics Content .....................................................................................................................................18 Building Polynomial Functions .....................................................................................................................19 Operations with Polynomials Worksheet .......................................................................................................22 Polynomial Puzzler ........................................................................................................................................24 Pascal’s Triangle Task ...................................................................................................................................25 Polynomial 1 Bell Quiz..................................................................................................................................27 Polynomial 2 Bell Quiz..................................................................................................................................28 Polynomial 3 Bell Quiz..................................................................................................................................29 4.3 FACTORING POLYNOMIALS ...........................................................................................................30 Teacher Notes ................................................................................................................................................30 Option 1: Polynomial Factoring Practice Worksheet.................................................................................32 Option 2: Polynomial Puzzle .....................................................................................................................33 Factoring Bell Quiz 1 .................................................................................................................................34 Mathematics Content .....................................................................................................................................35 NUCC | Secondary II Math ii Polynomial Factoring Practice .......................................................................................................................36 4.4 FACTORING SPECIAL PRODUCTS ..................................................................................................37 Teacher Notes ................................................................................................................................................37 Option 1. Special Products Factoring Worksheet ......................................................................................41 Option 2. Special Products and Factoring Task .........................................................................................42 Option 3. I Have, Who Has Factoring Worksheet .....................................................................................43 Special Products Bell Quiz 1 .....................................................................................................................44 Mathematics Content .....................................................................................................................................45 Patterns with Polynomial Products ................................................................................................................46 Special Products Factoring Worksheet ..........................................................................................................47 Special Products and Factoring Task .............................................................................................................49 I Have, Who Has Factoring Worksheet .........................................................................................................55 Special Products Bell Quiz ............................................................................................................................58 4.5 INTRO TO COMPLEX NUMBERS .....................................................................................................59 Teacher Notes ................................................................................................................................................59 John and Betty’s Story ...............................................................................................................................59 Ready, Set, Go! ..........................................................................................................................................61 Complex Numbers Worksheet ...................................................................................................................61 Mathematics Content .....................................................................................................................................62 Complex Numbers: ........................................................................................................................................63 The Story of John and Betty Guided Notes ...................................................................................................64 4.6 OPERATIONS WITH COMPLEX NUMBERS ...................................................................................65 Teacher Notes ................................................................................................................................................65 Mix –N –Match ..........................................................................................................................................65 Assign Ready, Set, Go! Worksheet ............................................................................................................67 Mathematics Content .....................................................................................................................................68 Teacher’s Master of Mix –N –Match.............................................................................................................69 Student copy of Mix –N –Match....................................................................................................................70 Ready, Set, Go! ..............................................................................................................................................71 H4.7 FACTORING WITH COMPLEX NUMBERS .....................................................................................72 Teacher Notes ................................................................................................................................................72 Mathematics Content .....................................................................................................................................74 Ready, Set, Go! ..............................................................................................................................................75 Practice Exam Secondary II Unit 4 ....................................................................................................................76 Exam Secondary II Unit 4..................................................................................................................................78 NUCC | Secondary II Math iii Unit 4.1 4.1 STRUCTURE OF EXPRESSIONS Teacher Notes Time Frame: One 40 minute class period Materials Needed: Scissors Note: This will be a review lesson for most students, except possibly the degree of a polynomial and the types of polynomials. Launch Triple Match Print one copy for each pair of students. Instructions: Students will work in pairs and cut out the terms and match the vocabulary word with the definition and an example. Select students to present their answers to the class. (Students should have learned these terms previously.) Explore Dealing with Expressions expression = mathematical phrase that contains operations, numbers and/or variables. (no =) Examples of expressions: 4, 4 + d, 𝟓𝒎𝟐 − 𝟐𝒎, k Write an algebraic expression for “6 apples and 2 mangos”. 6a + 2m Write an English statement for 2+𝑚2 3 . The sum of 2 and m squared divided by 3. NUCC | Secondary II Math 1 Unit 4.1 Use Algebra Tiles to model the expression: 3𝑥 2 + 𝑥 − 2 . Draw your model. Algebra tiles help connect what is happening with polynomials visually. They also connect geometry and algebra using area. This website has an excellent PowerPoint on the use of algebra tiles. http://mathbits.com/mathbits/AlgebraTiles/AlgebraTiles.htm * monomial = a number or variable or the product of numbers and variables. Also called a term. Examples of monomials: 4, k, 𝟓𝒎𝟐 polynomial = a monomial or the sum or difference of monomials. Examples of polynomials: 4, 4 + d, 𝟓𝒎𝟐 − 𝟐𝒎, k compare and contrast expressions and polynomials Discuss Polynomial Anatomy 101 𝑬𝒙: 𝟑𝒙𝟐 − 𝒙 + 𝟕 . Parts of a polynomial term = parts of the polynomial that are added or subtracted. (terms in the example are 𝟑𝒙𝟐 , −𝒙, 𝟕) variable = unknown quantity represented by a symbol, usually a letter. (variable in the example is x) coefficient = a number multiplied by a variable. (coefficients in the example are 3 and –1) operation = adding, subtracting, multiplying or dividing. (Operations in the example are multiplying, subtracting and adding) constant = unchanging, a term with only a number. (constant in the example is 7) degree = the highest degree of the terms of the polynomial. (degree in the example is 2) State the degree of each polynomial. * Find the degree of each term and the highest degree is the degree of the polynomial. Ex. 4𝑥 + 2𝑥 3 − 𝑥 2 + 11 1 3 2 0 Ex. 3𝑎𝑏 4 + 4𝑎5 𝑏 2 − 𝑎7 𝑏 5 3 7 8 8 Write the polynomial 𝑥 4 𝑦 + 2𝑥 5 − 3𝑥 + 9𝑥 3 𝑦 6 in standard form in regards to x. 𝟐𝒙𝟓 + 𝒙𝟒 𝒚 + 𝟗𝒙𝟑 𝒚𝟔 − 𝟑𝒙 NUCC | Secondary II Math 2 Unit 4.1 Types of polynomials (named by the degree of the polynomial) linear = degree of 1 (Ex: 4x + 7) quadratic = degree of 2 (Ex: 𝟐𝒙𝟐 + 𝟓𝒙 − 𝟔) cubic = degree of 3 (Ex: 𝟐𝒙𝟑 + 𝟐𝒙𝟐 − 𝟓𝒙 − 𝟔) * (leave the degree of 4 and 5 for the student to research) Assignment: Ready, Set Reviewing expressions NUCC | Secondary II Math 3 Unit 4.1 Classroom Activity: Go! Group Task Expressions 1 Bell Quiz and Answers NUCC | Secondary II Math 4 Unit 4.1 Mathematics Content Cluster Title: Interpret the structure of expressions. Standard A.SSE.1: Interpret expressions that represent a quantity in terms of its context. a. Interpret parts of an expression, such as terms, factors, and coefficients. b. Interpret complicated expressions by viewing one or more of their parts as a single entity. (For example, interpret P(1 + 4)n as the product of P and a factor not depending on P.) Concepts and Skills to Master Identify the parts of an expression, such as terms, factors, and coefficients, bases, exponents, and constant. Explain the meaning of the part in relationship to the entire expression and to the context of the problem. Understand that the product of two binomials is the sum of monomial terms. For example the product of (3x + 2) and (x – 5) is the sum of 3x2, -13x, and -10. Critical Background Knowledge Understand the meaning of symbols indicating mathematical operations, implied operations, the meaning of exponents, and grouping symbols. Understand the meaning of a rational exponent (Secondary II: N.RN.2). Academic Vocabulary Factors, coefficients, terms, exponent, base, constant, variable, binomial, monomial, polynomial Suggested Instructional Strategies Connect to quadratic functions and transformations. Identify the role of the part in possible transformations. Example: What role do j and k play in (x – h)2 + k ? Connect to area models. Skills: Given the quadratic 25x^2 + 30x + 9, justify that it is a perfect square trinomial. Use what you know about square roots to rewrite x2 – 6 as a difference of two squares. Some Useful Websites: http://mathbits.com/mathbits/AlgebraTiles/AlgebraTiles.htm NUCC | Secondary II Math 5 Unit 4.1 Triple Match NUCC | Secondary II Math 6 Unit 4.1 Name ________________________________________________ Period _________ Date _____________________ Ready, Set Ready Write an algebraic expression for each statement. 1. Fifteen apples plus 4 bananas. 2. Five ipods minus a computer. Write an English statement for each algebraic expression. 3. 4. (x + 7)(x – 4) 5𝑚2 6 +𝑚 Use Algebra Tiles to model the expressions. Draw your model. 5. 5𝑥 2 + 𝑥 + 2 6. 𝑥 2 − 4𝑥 + 3 7. 3𝑥 − 6 8. 3𝑥 − 2𝑥 2 Set State the degree of each polynomial. 9. 2𝑥 + 𝑥 3 − 5𝑥 2 + 8 10. 5𝑎𝑏 3 + 4𝑎7 − 𝑎2 𝑏 11. 𝑥 3 𝑦 5 + 3𝑥 4 𝑦 3 − 𝑥 5 12. 2𝑥 2 + 4𝑥 − 𝑥 5 − 1 13. 2𝑥 + 2 14. 5 NUCC | Secondary II Math 7 Unit 4.1 If possible, determine 2 polynomials with a sum and product that have the following degrees. 15. The sum has a degree of 2 and the product has a degree of 4. 16. The sum has a degree of 3 and the product has a degree of 5. 17. The sum has a degree of 2 and the product has a degree of 6. 18. The sum and the product have the same degree. 19. Complete the table. DEGREE POLYNOMIAL NAME EXAMPLE BASIC GRAPH SHAPE 1 2 3 4 5 State each polynomial in standard form in regard to x. 20. x 8 + 2x 4 − 6x 7 + x 21. x 3 yz + yz + x 2 y 3 z − x 22. 4 − 2x 2 + 3x 4 + x 3 23. 5x 3 y + 6x 5 − 4x + x 7 y 2 24. xy 5 + 6x 2 − x 3 y 25. 2x − 𝑥 2 + 𝑥 3 + 3 NUCC | Secondary II Math 8 Unit 4.1 Go! Names in group ________________________________________________ Period ___________ Date _____________________ 1. Dinner is served every night at St. Ann’s shelter. Write an expression for each of the supplies St. Ann’s may need to serve dinner. a. For each person, St. Ann’s needs ¼ cup of uncooked rice. b. For every 10 adults, St. Ann’s needs 0.8 loaves of bread. c. St. Ann’s needs half a pound of meat for every 3 people. d. For each person, 2.3 cups of beverages are needed. e. 9 more sets of dishes are needed than the number of people. f. For every 25 people, St. Ann’s needs 2 servers. Complete the table so that it may be used as a quick reference for St. Ann’s shelter. EXPRESSION 50 PEOPLE 100 PEOPLE 250 PEOPLE RICE BREAD MEAT BEVERAGES DISHES SERVERS 2. Why are expressions useful? 3. Why are variables useful? NUCC | Secondary II Math 9 Unit 4.1 Expressions and Number Tricks 4. Choose a number. Add 4. Subtract 2. Multiply by 2. Subtract 4. Write your number and your solution. a. Choose 3 more numbers and follow the same processes as you did in problem 4. Write your numbers and their solutions. b. What did you notice? c. Write an expression for this math problem. 5. As a group make up a number trick with at least 4 steps, you will be presenting your trick to the class and we will try to figure out how it works. . NUCC | Secondary II Math 10 Unit 4.1 Name ________________________________________________ Period _________ Date _____________________ Expressions 1 Bell Quiz Combine like terms. 1. 𝟒𝒙𝟐 + 𝟓𝒙𝟐 + 𝒙 2. 𝟕𝒙𝒚 − 𝒙 + 𝟓𝒚 − 𝟗𝒙𝒚 + 𝒚 3. 𝟖 − 𝟑𝒙𝟓 + 𝟔𝒙𝟒 + 𝟏𝟐 + 𝒙𝟓 4. 𝟑𝒙 − 𝟗𝒙 + 𝟑𝒙 + 𝒙 + 𝟏𝟑𝒙 5. 𝟔𝒙𝒚𝟐 − 𝟏𝟓𝒙𝟐 𝒚 + 𝒙𝟐 𝒚 − 𝟒𝒙𝒚𝟐 + 𝒙𝒚𝟐 NUCC | Secondary II Math 11 Unit 4.2 4.2 OPERATIONS WITH POLYNOMIALS Teacher Notes Time Frame: Two 40 minute class periods Materials Needed: Colored pencils, rulers or strips of paper, graphing calculators (optional) Note: This will be a review lesson for most students, except dividing polynomials. Launch Building Polynomial Functions Activity Reference: http://illuminations.nctm.org/LessonDetail.aspx?id=L282. Encourage students to work in pairs on the activity sheets. Each student needs the activity sheets, three different colored pencils, and a strip of paper or a ruler. The discussion generated by questions in the activity is beneficial. Students start by identifying a linear function and putting the equation in slope/x-intercept form, y = m(x - c), where c is the x-intercept. This form serves as a connector with other classes of polynomial functions and forces students to focus on the x-intercept of the graph. They then choose another function in the form y = m(x - c) and graph this function on the same axes. Students predict how a new function, formed by taking the product of the two linear expressions, would appear graphically. After making their prediction, they graph the resulting quadratic function and compare the actual function with their prediction. Students can use a graphing utility to check the function formed by taking the product of the linear factors, but only after making the prediction. Activity questions that compare the linear functions with the resulting quadratic function focus the students' attention on the parts of the graphs to be emphasized. Students learn that the quadratic function has the same x-intercepts as the linear functions, which can be quite a revelation, and that the y-intercept of the quadratic function is the product of the y-intercepts of the linear functions. In fact, the y-coordinate of the parabola for a given x-value is always the product of the y-coordinates of 12 Resources for Teaching Math © 2009 National Council of Teachers of Mathematics http://illuminations.nctm.org Unit 4.2 the lines for that x-value. Seeing this relationship is easier when x equals 0 and the y-coordinates are lined up on the y-axis. Students then use a strip of paper or a ruler to cover parts of the graph. This part of the activity shows that the sign of the y-coordinate for any point on the parabola can be determined by observing whether the y-coordinates of the lines for that section of the graph are positive or negative. For example, if both lines in a section of the graph are above the x-axis, then the parabola will be above the x-axis, that is, (+) • (+) = (+). If one line in a section of the graph is above the x-axis and the other is below the x-axis, then the parabola is below the x-axis, that is, (+) • (–) = (–). This result corresponds to the sign table that students have traditionally used as an aid to graph functions and inequalities. Discuss Have students verbally define a polynomial. polynomial = a monomial or the sum or difference of monomials. Examples of polynomials: 4, 4 + d, 𝟓𝒎𝟐 − 𝟐𝒎, k * compare and contrast expressions and polynomials Examples in writing a polynomial Write a polynomial where each term is a different degree and the polynomial is linear with 2 terms. How about quadratic with 2 terms? Possible answers: 4x + 9, 𝟒𝒙𝟐 − 𝟗 Using Algebra Tiles Algebra tiles help connect what is happening with polynomials visually. They also connect geometry and algebra using area. This website has an excellent PowerPoint on the use of algebra tiles. If no tiles are available students may just draw in the tile solution. http://mathbits.com/mathbits/AlgebraTiles/AlgebraTiles.htm 13 Resources for Teaching Math © 2009 National Council of Teachers of Mathematics http://illuminations.nctm.org Unit 4.2 Examples to do with tiles and without tiles: Adding and Subtracting (putting together like terms!) 𝟐𝒙𝟐 − 𝒙 + 𝒙𝟐 − 𝟓𝒙 𝟑𝒙𝟐 − 𝟒𝒙 𝟑𝒙 − 𝟏 + 𝟐𝒙 + 𝟑𝒙𝟐 + 𝟒 𝟑𝒙𝟐 + 𝟓𝒙 + 𝟑 Multiplying (distributing, (𝒙 + 𝟏)𝟑 𝒑𝒓𝒐𝒃𝒍𝒆𝒎𝒔 𝒍𝒊𝒌𝒆 𝒕𝒉𝒊𝒔 𝒊𝒕 𝒊𝒔 𝒂𝒍𝒔𝒐 𝒄𝒂𝒍𝒍𝒆𝒅 𝒆𝒙𝒑𝒂𝒏𝒅𝒊𝒏𝒈) 𝟒𝒙(𝒙 + 𝟑) (𝒙 + 𝟑)(𝟐𝒙 + 𝟐) 𝟒𝒙𝟐 + 𝟏𝟐𝒙 𝟐𝒙𝟐 + 𝟐𝒙 + 𝟔𝒙 + 𝟔 𝟐𝒙𝟐 + 𝟖𝒙 + 𝟔 Students will have seen adding, subtracting and multiplying polynomials in Secondary I. We did not cover dividing polynomials so they may need additional help on this operation. This is a website that explains dividing polynomials. http://www.youtube.com/watch?v=qd-T-dTtnX4 (𝒙𝟐 + 𝟑𝒙 + 𝟐) ÷ (𝒙 + 𝟏) Dividing x+2 𝒙+𝟏 𝒙𝟐 + 𝟑𝒙 + 𝟐 −𝒙𝟐 + 𝒙 2x + 2 Assignment Ready, Set (Operations with Polynomials Worksheet) 14 Resources for Teaching Math © 2009 National Council of Teachers of Mathematics http://illuminations.nctm.org Unit 4.2 Assignment Go! (Use either option) Option 1: Polynomial Puzzles Task For more information and detailed instructions on Polynomial Puzzles see the website. There is also an overhead sheet to walk the students through (see below). (May be used in Unit 4.3, if not used here) Reference: http://illuminations.nctm.org/LessonDetail.aspx?id=L798 Polynomial Puzzle Overhead Polynomial Puzzle Answers for Overhead Student’s worksheet: 15 Resources for Teaching Math © 2009 National Council of Teachers of Mathematics http://illuminations.nctm.org Unit 4.2 Option 2: Pascal’s Triangle Task Polynomial Bell Quiz 1 NUCC | Secondary II Math 16 Unit 4.2 Polynomial Bell Quiz 2 Polynomial Bell Quiz 3 NUCC | Secondary II Math 17 Unit 4.2 Mathematics Content Cluster Title: Perform arithmetic operations on polynomials. Standard A.ARP.1: Understand that polynomials form a system analogous to the integers – namely, they are closed under the operations of addition, subtraction, and multiplication; add, subtract, and multiply polynomials. Concepts and Skills to Master Add and subtract polynomials. Multiply polynomials using the distributive property, and then simplify. Understand closure of polynomials for addition, subtraction, and multiplication. Critical Background Knowledge Understand operations and properties of integers, including closure. Add and subtract like terms. Understand the distributive property. Academic Vocabulary Like terms, binomial, trinomial, polynomial, closure Suggested Instructional Strategies Use algebra tiles or other manipulatives for addition, subtraction, and multiplication of polynomials. Try to find two polynomials whose sum/product is not a polynomial. Skills: Multiply (x2 + 3x – 5)(x + 4) and determine if the result is a polynomial. Some Useful Websites: http://illuminations.nctm.org/LessonDetail.aspx?id=L282 http://mathbits.com/mathbits/AlgebraTiles/AlgebraTiles.htm http://www.youtube.com/watch?v=qd-T-dTtnX4 http://illuminations.nctm.org/LessonDetail.aspx?id=L798 http://mathforum.org/workshops/usi/pascal/pascal_binomial.html NUCC | Secondary II Math 18 Unit 4.2 Building Polynomial Functions Name ________________________________________________ Period _________ 1. What is the equation of the linear function shown to the right? 2. How did you find it? 3. The slope – y-intercept form of a linear function is y = mx + b. If you’ve written the equation in another form, rewrite your equation in slope – y-intercept form. 4. Now, factor out the slope, and rewrite the function y = m ( x + b ) . as m 5. Choose a second linear function and write it in slope – y-intercept form. 6. Graph the function on the axis above, and be sure to label it. 7. Rewrite your second function with the slope factored out (just like you did in Question 4). 8. For each function, what does represent on the graph? m b y = m ( x − c ) could be called the slope – x-intercept form of a linear If you let c =m− b , then the form equation, where c is the x-intercept. The factor theorem states that if c is a root (x-intercept) of a polynomial function, then ( x − c) must be a factor of that polynomial function. Note that ( x − c) is a factor of the expression. The only other factor is the slope m. 9. From their slope – y-intercept form, multiply the two functions together. 19 Resources for Teaching Math © 2009 National Council of Teachers of Mathematics http://illuminations.nctm.org Unit 4.2 10. Graph the resulting function on the same axis as the two lines on the previous page. 11. What kind of function did you get? 12. What relationship do you see between the graph from Question 10 and the lines? • …and the x-intercepts? • …and the y-intercepts? 13. Identify the left-most x-intercept on the graph. With a straight-edge, cover everything to the right of that point. What connections do you see relating the signs of the y-values? 14. Identify the right-most intercept on the graph. With a straight-edge, cover up everything to the left of that point. What connections do you see relating to the signs of the y-values? Complete the following sentences. 15. When both lines are above the x-axis, the y-values are parabola . and the 16. When both lines are below the x-axis, the y-values are parabola . and the 17. When one line is above the x-axis and the other is below the x-axis, the parabola . y-VALUE OF L1 y-VALUE OF L2 + + - + + - PARABOLA IS ABOVE/BELOW THE x-AXIS 20 Resources for Teaching Math © 2009 National Council of Teachers of Mathematics http://illuminations.nctm.org Unit 4.2 18. Based on the patterns you saw on the previous page, draw a sketch of the quadratic function that would be obtained from the linear expressions of these lines. 19. Write the equation for each line. 20. To check your sketch in Question 18, multiply the expressions together, and graph the resulting function on the grid above. How accurate was your sketch? 21 Resources for Teaching Math © 2009 National Council of Teachers of Mathematics http://illuminations.nctm.org Unit 4.2 Operations with Polynomials Worksheet Name ________________________________________________ Period _________ Anatomy of a Polynomial Identify the following terms from the polynomial, 𝒙𝟐 − 𝒙 + 𝟔 . 1. variable(s) 2. coefficient(s) 3. operation(s) Write a polynomial where each term is a different degree and the polynomial satisfies each condition. 4. linear polynomial with 1 term 5. linear polynomial with 2 terms 6. quadratic polynomials with 3 terms 7. cubic polynomials with 4 terms Use Algebra Tiles to perform the following operations. Draw the algebra tile solution and then write the solution. 8. 5𝑥 2 − 4𝑥 + 𝑥 2 − 2𝑥 9. 3𝑥 − 6 + 6𝑥 − 𝑥 2 + 4 10. 3𝑥(2𝑥 + 3) 11. 2𝑥(4𝑥 + 1) 12. (𝑥 + 1)(𝑥 + 3) 13. (𝑥 + 2)(2𝑥 + 1) 14. (2𝑥 2 + 4𝑥 + 3) ÷ (𝑥 + 1) 15. (4𝑥 2 + 6𝑥 + 2) ÷ (2𝑥 + 2) NUCC | Secondary II Math 22 Unit 4.2 Adding and Subtracting Polynomials 16. 2𝑎2 + 5𝑎2 + 𝑎 17. 4𝑚𝑛 − 3𝑚 + 2𝑛 − 9𝑚𝑛 + 𝑛 18. 6 − 𝑘 5 + 4𝑘 4 + 9 + 𝑘 5 19. 2𝑥 − 9𝑥 + 4𝑥 + 𝑥 + 2𝑥 20. 𝑎𝑏 − 7𝑎𝑏 + 𝑎𝑏 + 8𝑎𝑏 2 21. 4𝑥𝑦 2 − 9𝑥 2 𝑦 + 𝑥 2 𝑦 + 7𝑥𝑦 2 + 𝑥𝑦 2 Multiplying Polynomials 22. 8𝑚𝑛(5𝑚 + 3𝑛 − 6) 23. 3𝑥𝑦 2 (4𝑥 − 7𝑥𝑦) 24. (3𝑥 − 1)(𝑥 + 6) 25. (𝑥 − 7)(𝑥 + 7) 26. 𝑥(𝑥 + 2)(𝑥 − 5) 27. 2𝑥(𝑥 − 10)(𝑥 2 − 4) 28. (𝑥 + 3)3 29. (2𝑥 − 1)4 Dividing Polynomials 30. (6𝑚𝑛2 − 3𝑚𝑛 + 2𝑥 2 𝑦) ÷ (𝑥𝑦) 31. (𝑘 2 − 10𝑘 − 24) ÷ (𝑘 + 2) 32. (𝑥 3 + 𝑦 3 ) ÷ (𝑥 + 𝑦) 33. (𝑡 2 + 8𝑡 + 15)(𝑡 + 3)−1 34. (𝑥 3 + 3𝑥 2 − 7𝑥 − 21)(𝑥 + 3)−1 35. (60𝑚2 − 98𝑛2 ) ÷ (10𝑚 + 14𝑛) Prove each Identity 36. 𝑥 2 − 𝑦 2 = (𝑥 + 𝑦)(𝑥 − 𝑦) 37. (𝑥 + 𝑦)2 = 𝑥 2 + 2𝑥𝑦 + 𝑦 2 NUCC | Secondary II Math 23 Unit 4.2 Polynomial Puzzler Name ________________________________________________ Period _________ Fill in the empty spaces to complete the puzzle. In any row, the two left spaces should multiply to equal the right-hand space. In any column, the two top spaces should multiply to equal the bottom space. 1. 2. 3. 4. 5. 6. 24 Resources for Teaching Math © 2009 National Council of Teachers of Mathematics http://illuminations.nctm.org Unit 4.2 Pascal’s Triangle Task Group Members ________________________________________________ Period _____ A. Determine the pattern and then complete rows 5, 6 and 7 of the triangle. Row Number Pascal’s Triangle 0 1 1 1 2 1 3 1 4 ___ ___ 6 7 ___ 4 ___ ___ ___ 2 3 1 5 1 3 6 ___ ___ ___ 1 4 ___ ___ ___ 1 1 ___ ___ ___ ___ ___ ___ ___ ___ ___ B. Multiply the following binomials. 1. (𝑥 + 𝑦)0 2. (𝑥 + 𝑦)1 3. (𝑥 + 𝑦)2 4. (𝑥 + 𝑦)3 5. (𝑥 + 𝑦)4 NUCC | Secondary II Math 25 Unit 4.2 C. What is the connection between the expanded binomials and the Pascal’s Triangle? D. Expand (multiply) the binomials using Pascal’s Triangle. 1. (𝑥 + 𝑦)6 2. (𝑥 + 𝑦)7 3. (𝑥 + 𝑦)8 E. Prepare a 2 minute presentation about Pascal’s triangles and binomial expansions. Write your presentation here and be creative. Reference: http://mathforum.org/workshops/usi/pascal/pascal_binomial.html Extension: How can we use Pascal's triangle to write the expansion of any binomial (x+y)n. NUCC | Secondary II Math 26 Unit 4.2 Name ________________________________________________ Period _________ Date _____________________ Polynomial 1 Bell Quiz Write an expression for each statement. 1. Six lemons and 4 pickles 2. The quotient of the sum of five and a number and nine Write a statement for the expression. 3. 𝟐 + 𝒙𝟓 4. 5. 𝒎−𝟒 𝟑 Write an expression with 3 different operations where you begin with the number 5 and end with 23. NUCC | Secondary II Math 27 Unit 4.2 Name ________________________________________________ Period _________ Date _____________________ Polynomial 2 Bell Quiz Identify the following terms from the polynomial 𝟑𝒙𝟐 − 𝟒𝒙 + 𝟏𝟑. 1. Constant(s) 2. Coefficient(s) 3. Degree Write a polynomial where each term is a different degree and the polynomial satisfies each condition. 4. Linear polynomial with 1 term 5. Quadratic polynomial with 3 terms NUCC | Secondary II Math 28 Unit 4.2 Name ________________________________________________ Period _________ Date _____________________ Polynomial 3 Bell Quiz Multiply the polynomials. 1. 𝟐𝒙(𝒙𝟐 + 𝟓) 2. 𝟑𝒙𝒚(𝒙 + 𝟓𝒚 − 𝟐𝒙𝒚) 3. (𝒙 + 𝟓)(𝒙 + 𝟐) 4. (𝟐𝒙 − 𝟑)(𝒙 + 𝟏) 5. 𝟒𝒙(𝒙 + 𝟑)(𝟑𝒙 − 𝟐) NUCC | Secondary II Math 29 Unit 4.3 4.3 FACTORING POLYNOMIALS Teacher Notes Time Frame: Two 40-minute class periods Materials Needed: Launch: Number Factor Relay Divide the room in half and give each student a number. Give the other side of the room the same numbers. You can set up more teams if you want, however, 2 is usually good. For the relay you will put a number to be factored on the whiteboard and then call out a number so that both students with that number come to the board to factor. It is a race to see who can write all the factors the quickest. There may be more than one possible answer. The winning team gets a point. If neither student can figure out the factors call another number up to assist them. 10 minutes should get through a class. Example: Write the number 38 on board, call out number 4, number 4 students come to the board and write 2 and 19. *Students should know factors. Discuss Ready A. Greatest Common Factor (Students should know this, but may need reminded. Show them the method below, but most students can pull out the greatest common factors by observation.) Ex: 4𝑥 2 + 20𝑥 Write the factors for each term and circle the factors in common. The greatest common factor goes in front of the parentheses and the remaining numbers stay inside the parentheses. 2∙2∙𝑥∙𝑥 𝟒𝒙(𝒙 + 𝟓) 2∙2∙5∙𝑥 More Examples: 14𝑚 − 21𝑚3 𝑛 𝟕𝒎(𝟐 − 𝟑𝒎𝟐 𝒏) 18𝑡𝑟 2 + 9𝑟 𝟗𝒓(𝟐𝒕𝒓 + 𝟏) 3𝑥 2 − 6𝑥 + 12𝑥 3 𝟑𝒙(𝒙 − 𝟐 + 𝟒𝒙𝟐 ) *Remind students to always look to see if the terms of the polynomial have a common factor first!!!! NUCC | Secondary II Math 30 Unit 4.3 Set B. Trinomials (Students may or may not have learned this. Experience is usually minimal.) 1. Leading coefficient of 1 Vocab Reminders trinomial = polynomial with 3 terms. A type of quadratic equation. leading coefficient = the number multiplied to the variable of the first term of a polynomial in standard form. Ex: 2𝑥 2 + 𝑥 + 3 is a trinomial and the leading coefficient is 2 Procedure: Use 2 factors of the constant term that you can add to get the coefficient of the second term. Ex: 𝑥 2 + 6𝑥 + 8 factors are (𝑥 + 4)(𝑥 + 2) Note 4 ∙ 2 = 8 𝑎𝑛𝑑 4 + 2 = 6 *Do one example of multiplying the factors back out to get the trinomial as a check. More examples for student practice: 𝑥 2 − 2𝑥 − 8 𝑓𝑎𝑐𝑡𝑜𝑟𝑠 𝑎𝑟𝑒 (𝑥 − 4)(𝑥 + 2) , − 4 ∙ 2 = −8 𝑎𝑛𝑑 − 4 + 2 = −2 𝑥 2 − 6𝑥 + 8 𝑓𝑎𝑐𝑡𝑜𝑟𝑠 𝑎𝑟𝑒 (𝑥 − 4)(𝑥 − 2) , − 4 ∙ −2 = 8 𝑎𝑛𝑑 − 4 + (−2) = −6 𝑥2 − 𝑥 − 6 𝑓𝑎𝑐𝑡𝑜𝑟𝑠 𝑎𝑟𝑒 (𝑥 − 3)(𝑥 + 2) , − 3 ∙ 2 = −6 𝑎𝑛𝑑 − 3 + 2 = −1 𝑥 2 + 5𝑥 − 6 𝑓𝑎𝑐𝑡𝑜𝑟𝑠 𝑎𝑟𝑒 (𝑥 − 6)(𝑥 + 1) , − 6 ∙ 1 = −6 𝑎𝑛𝑑 − 6 + 1 = 5 𝑥 2 + 𝑥 − 56 𝑓𝑎𝑐𝑡𝑜𝑟𝑠 𝑎𝑟𝑒 (𝑥 − 7)(𝑥 + 8) , − 7 ∙ 8 = −56 𝑎𝑛𝑑 − 7 + 8 = 1 Extra explanation at: http://www.regentsprep.org/regents/math/algebra/AV6/Ltri1.htm 2. Leading coefficients other than 1: Procedure: a. Multiply the leading coefficient by the constant term. b. Multiply to get the constant term and add those same 2 numbers to get the second term coefficient. c. Divide the leading coefficient back out from the numerical part of the factors and simplify. Ex: 3𝑥 2 + 10𝑥 + 8 a. 3 ∙ 8 = 24 𝑠𝑜 𝑎𝑑𝑗𝑢𝑠𝑡𝑒𝑑 𝑡𝑟𝑖𝑛𝑜𝑚𝑖𝑎𝑙 𝑖𝑠 𝑥 2 + 10𝑥 + 24 b. factors of adjusted trinomial are (𝑥 + 4)(𝑥 + 6) 4 6 4 c. (𝑥 + 3)(𝑥 + 3) (You can leave the (𝑥 + 3) as it is easier to find the zeros, but tradition moves the denominator in front of the x) NUCC | Secondary II Math 31 Unit 4.3 (3𝑥 + 4)(𝑥 + 2) (multiply this one back out to check work) More examples for student practice: 5𝑥 2 + 13𝑥 − 6 𝑓𝑎𝑐𝑡𝑜𝑟𝑠 𝑎𝑟𝑒 (5𝑥 − 2)(𝑥 + 3) 4𝑥 2 + 19𝑥 + 15 𝑓𝑎𝑐𝑡𝑜𝑟𝑠 𝑎𝑟𝑒 (𝑥 + 1)(4𝑥 + 15) 3 𝑥 2 − 2𝑥 − 8 𝑓𝑎𝑐𝑡𝑜𝑟𝑠 𝑎𝑟𝑒 (3𝑥 + 4)(𝑥 − 2) 9 𝑥 2 − 15𝑥 + 4 𝑓𝑎𝑐𝑡𝑜𝑟𝑠 𝑎𝑟𝑒 (3𝑥 − 4)(3𝑥 − 1) Go! (Do one or both options for practice) Option 1: Polynomial Factoring Practice Worksheet NUCC | Secondary II Math 32 Unit 4.3 Option 2: Polynomial Puzzle For more information and detailed instructions on Polynomial Puzzles see the website. There is also an overhead sheet to walk the students through (see below). See Unit 4.2 for pages to copy. http://illuminations.nctm.org/LessonDetail.aspx?id=L798 Polynomial Puzzle Overhead Polynomial Puzzle Answers for Overhead Student’s worksheet: NUCC | Secondary II Math 33 Unit 4.3 Factoring Bell Quiz 1 NUCC | Secondary II Math 34 Unit 4.3 Mathematics Content Cluster Title: Write expressions in equivalent forms to solve problems. Standard A.SSE.3: Choose and produce an equivalent form of an expression to reveal and explain properties of the quantity represented by the expression.★ a. Factor a quadratic expression to reveal the zeros of the function it defines. b. Complete the square in a quadratic expression to reveal the maximum or minimum value of the function it defines. c. Use the properties of exponents to transform expressions for exponential functions. (For example the expression 1.15t can be rewritten as (1.151/12)12t - 1.01212t to reveal the approximate equivalent monthly interest rate if the annual rate is 15%.) Concepts and Skills to Master • • Rewrite expressions in different forms using mathematical properties. Given a context determine the best form of an expression. Critical Background Knowledge • • Understand the distributive property in simplifying and expanding expressions. Various types of factoring skills. Academic Vocabulary factors, coefficients, terms, exponent, base, constant, variable, binomial, monomial, polynomial Suggested Instructional Strategies • • Connect point-slope form to transformation of a line. Connect to the forms of a quadratic function. Skills: • • • • Given a quadratic in standard form, rewrite in vertex form and list the properties used in each step. One of the factors of 0.2x3 – 1.2x2 -0.6x is (x-2). Find the other factors. Find multiple ways to rewrite x6 – y6. 2 Rewrite in radical form 𝑥 ⁄3 in radical form. Some Useful Websites: http://illuminations.nctm.org/LessonDetail.aspx?id=L798 http://www.regentsprep.org/regents/math/algebra/AV6/Ltri1.htm NUCC | Secondary II Math 35 Unit 4.3 Name ________________________________________________ Period _________ Polynomial Factoring Practice Factor each polynomial completely. 1. 𝟔𝟒𝐚𝟐 𝐛𝟑 − 𝟏𝟔𝐛𝟐 𝐚𝟑 2. 𝐱 𝟐 + 𝟐𝟎𝐱 + 𝟏𝟎𝟎 3. 𝟑𝐱 𝟐 − 𝟐𝐱 − 𝟓 4. 𝟐𝐧𝟐 + 𝟓𝐧 + 𝟐 5. 𝟏𝟒𝟒𝐱 𝟐 − 𝟏𝟎𝟖𝐲 𝟐 − 𝟔𝟎𝐳 𝟐 6. 𝟑𝐰 𝟐 − 𝟖𝐰 + 𝟒 7. 𝟓𝐦𝟑 𝐧 + 𝟏𝟓𝐦𝐧𝟐 8. 𝟐𝐦𝟐 + 𝟏𝟏𝐦 + 𝟓 9. 𝟓𝐧𝟐 − 𝟏𝟖𝐧 + 𝟗 10. 𝟔𝐱 𝟑 𝐲 + 𝟏𝟐𝐱𝐲 11. 𝟏𝟓𝐳 𝟐 − 𝟐𝟕𝐳 − 𝟔 12. 𝐦𝟐 − 𝟕𝐦 + 𝟏𝟐 13. 𝟒𝐭 𝟐 − 𝟏𝟓𝐭 − 𝟐𝟓 14. 𝐤 𝟐 − 𝟓𝐤 − 𝟑𝟔 15. 𝟏𝟓𝐱 𝟐 − 𝟐𝟕𝐱 − 𝟔 16. 𝟑𝟒𝐱 𝟐 𝐲𝐳 𝟑 − 𝟏𝟕𝐱𝐲𝐳 17. 𝐤 𝟐 + 𝟏𝟏𝐤 + 𝟏𝟖 18. 𝟐𝟖𝐦𝐧𝟑 − 𝟏𝟒𝐦𝟐 𝐧 19. 𝐳 𝟐 − 𝟏𝟑𝐳 + 𝟑𝟔 20. 𝟒𝐱 𝟐 − 𝟑𝟓𝐱 + 𝟒𝟗 21. 𝟔𝐦𝟐 + 𝟑𝟕𝐦 + 𝟔 22. 𝟏𝟖𝐱𝐲 𝟑 − 𝟔𝐱𝐲 𝟐 23. 𝟔𝟗 + 𝟐𝟔𝐯 𝟑 − 𝟓𝟐𝐯 24. 𝐱 𝟐 − 𝐱 − 𝟑𝟎 Write a polynomial that has the given factors. 25. (𝟐𝐱 − 𝟑)(𝟒𝐱 + 𝟔) 26. 𝟕𝐱𝐲(𝟐𝐱 − 𝟗𝐱𝐲 𝟐 ) 27. (𝐱 − 𝟔)(𝐱 + 𝟕) NUCC | Secondary II Math 36 Unit 4.4 4.4 FACTORING SPECIAL PRODUCTS Teacher Notes Time Frame: Two 40-minute class periods Materials Needed: Launch: (15 minutes) Patterns with Polynomial Products Have the students work in groups to multiply out the sets of polynomials, there are 5 different sets, so some groups will be doing the same discovery. Tell the students to look for patterns in the sets (factors) and in the product. Students will be asked to present their discoveries to the class. The patterns students should discover are in the boxes to the right. NUCC | Secondary II Math 37 Unit 4.4 Discuss: 1. Difference of Two Squares a. (𝑥 + 4)(𝑥 − 4) b. (𝑥 + 2)(𝑥 − 2) Patterns Factor: One factor is adding and one is minus. The first letter is the same and the last number are the same for each factor. c. (𝑥 + 5)(𝑥 − 5) d. (𝑥 + 7)(𝑥 − 7) e. (𝑥 + 10)(𝑥 − 10) Product: Always subtracting The first letter and the last are squared. The middle terms cancel out 2. Perfect Square Sums a. (𝑥 + 4)(𝑥 + 4) b. (𝑥 + 2)(𝑥 + 2) Patterns Factor: Both factors are adding. Both factors are identical and could be written (𝑥 + 4)2 c. (𝑥 + 5)(𝑥 + 5) d. (𝑥 + 7)(𝑥 + 7) e. (𝑥 + 10)(𝑥 + 10) 3. Perfect Square Differences a. (𝑥 − 4)(𝑥 − 4) b. (𝑥 − 2)(𝑥 − 2) c. (𝑥 − 5)(𝑥 − 5) d. (𝑥 − 7)(𝑥 − 7) e. (𝑥 − 10)(𝑥 − 10) Product: The first and last terms are the squares of the first and last terms of the binomial The middle term is twice the product of the two terms in the binomial Only the adding operation in the product Patterns Factor: Both factors are subtracted Both factors are identical and could be written (𝑥 − 4)2 Product: The first and last terms are the of the first and last terms of the binomial The middle term is twice the product of the two terms in the binomial Operations of the product are always subtraction then addition NUCC | Secondary II Math 38 Unit 4.4 4. Sum of Two Cubes a. (𝑥 + 4)(𝑥 2 − 4𝑥 + 16) b. (𝑥 + 2)(𝑥 2 − 2𝑥 + 4) c. (𝑥 + 1)(𝑥 2 − 𝑥 + 1) d. (𝑥 + 3)(𝑥 2 − 3𝑥 + 9) Patterns Factor: Factors are binomial & trinomial Binomial is a sum Trinomial is subtracting then adding Middle term coefficient of trinomial is same as constant of the binomial Constant of trinomial is the square of the constant of the binomial Product: A sum The terms are each cubed 5. Difference of Two Cubes a. (𝑥 − 4)(𝑥 2 + 4𝑥 + 16) b. (𝑥 − 2)(𝑥 2 + 2𝑥 + 4) c. (𝑥 − 1)(𝑥 2 + 𝑥 + 1) d. (𝑥 − 3)(𝑥 2 + 3𝑥 + 9) Patterns Factor: Factors are binomial & trinomial Binomial is subtraction Trinomial is addition Middle term coefficient of trinomial is same as constant of the binomial Constant of trinomial is the square of the constant of the binomial Product: A difference The terms are each cubed Ready Conjugates = Two binomials with the same two terms but opposite signs separating the terms are called conjugates of each other. Following are examples of conjugates: Which special product has conjugates? Difference of 2 Squares NUCC | Secondary II Math 39 Unit 4.4 Have students make the following table in their notes and write examples from the leading task in the example column. SPECIAL PRODUCT FACTORING PATTERNS EXAMPLE POLYNOMIALS Difference of Two Squares 𝒂𝟐 − 𝒃𝟐 (𝒂 + 𝒃)(𝒂 − 𝒃) Perfect Square Sums 𝒂𝟐 + 𝟐𝒂𝒃 + 𝒃𝟐 (𝒂 + 𝒃)𝟐 Perfect Square Differences 𝒂𝟐 − 𝟐𝒂𝒃 + 𝒃𝟐 (𝒂 − 𝒃)𝟐 Sum of Two Cubes (𝒂 + 𝒃)(𝒂𝟐 − 𝒂𝒃 + 𝒃𝟐 ) 𝒂𝟑 + 𝒃𝟑 Difference of Two Cubes (𝒂 − 𝒃)(𝒂𝟐 + 𝒂𝒃 + 𝒃𝟐 ) 𝒂𝟑 − 𝒃𝟑 Set Practice factoring a few of each of the special products. 1. 𝑥 2 − 25 (𝑥 + 5)(𝑥 − 5) 2. 𝑥 2 − 81 (𝑥 + 9)(𝑥 − 9) 3. 𝑥 2 − 49 (𝑥 + 7)(𝑥 − 7) 4. 𝑥 2 + 12𝑥 + 36 5. 𝑥 2 + 4𝑥 + 4 (𝑥 + 6)2 (𝑥 + 2)2 NUCC | Secondary II Math 40 Unit 4.4 6. 𝑥 2 − 20𝑥 + 100 7. 𝑥 2 − 10𝑥 + 25 (𝑥 − 10)2 (𝑥 − 5)2 8. 𝑥 3 + 8 (𝑥 + 2)(𝑥 2 − 2𝑥 + 4) 9. 𝑥 3 + 1 (𝑥 + 1)(𝑥 2 − 𝑥 + 1) 10. 𝑥 3 − 27 (𝑥 − 3)(𝑥 2 + 3𝑥 + 9) 11. 𝑥 3 − 64 (𝑥 − 4)(𝑥 2 + 4𝑥 + 16) Go! (Do as many options as needed for your students) Option 1. Special Products Factoring Worksheet NUCC | Secondary II Math 41 Unit 4.4 Option 2. Special Products and Factoring Task (*Similar activity as the opening task. There are six pages to this task.) NUCC | Secondary II Math 42 Unit 4.4 Option 3. I Have, Who Has Factoring Worksheet The game is called “I have, who has factoring” It is a review game for factoring trinomials. (reviews factoring from units 4.1 through 4.4) This is a game that is found at http://www.ilovemath.org/index.php?option=com_docman&task=doc_details&gid=100 NUCC | Secondary II Math 43 Unit 4.4 Special Products Bell Quiz 1 NUCC | Secondary II Math 44 Unit 4.4 Mathematics Content Cluster Title: Interpret the structure of expressions. Standard A.SSE.2: Use the structure of an expression to identify ways to rewrite it. For example, see x4 – y4 as (x2)2 – (y2)2, thus recognizing it as a difference of squares that can be factored as (x2 – y2)(x2 + y2). Concepts and Skills to Master • • • Understand that an expression has different forms. Justify the different forms based on mathematical properties. Interpret different symbolic notation. Critical Background Knowledge • • Understand the distributive property in simplifying and expanding expressions. Various types of factoring skills. Academic Vocabulary factors, coefficients, terms, exponent, base, constant, variable, binomial, monomial, polynomial Suggested Instructional Strategies • This standard should be taught in conjunction with standard A.DDE.3, with heavy emphasis on justification. Skills: • Factor x6 – y6 as the difference of two squares and as the difference of cubes. Justify that the resulting expressions are equivalent. Some Useful Websites: Distributing and factoring using area: http://illuminations.nctm.org/LessonDetail.aspx?id=L744 Difference of squares: http://illuminations.nctm.org/LessonDetail.aspx?id=L276 NUCC | Secondary II Math 45 Unit 4.4 Patterns with Polynomial Products Have the students work in groups to multiply out the sets of polynomials, there are 5 different sets of polynomials, so some groups will be doing the same discovery. Tell the students to look for patters in the sets (factors) and in the product. Students will be asked to present their discoveries to the class. Cut the sets apart to give to the groups. a. (𝐱 + 𝟒)(𝐱 − 𝟒) a. (𝒙 + 𝟒)(𝒙 + 𝟒) b. (𝐱 + 𝟐)(𝐱 − 𝟐) b. (𝒙 + 𝟐)(𝒙 + 𝟐) c. (𝐱 + 𝟓)(𝐱 − 𝟓) c. (𝒙 + 𝟓)(𝒙 + 𝟓) d. (𝐱 + 𝟕)(𝐱 − 𝟕) d. (𝒙 + 𝟕)(𝒙 + 𝟕) e. (𝐱 + 𝟏𝟎)(𝐱 − 𝟏𝟎) e. (𝒙 + 𝟏𝟎)(𝒙 + 𝟏𝟎) a. (𝒙 − 𝟒)(𝒙 − 𝟒) a. (𝒙 + 𝟒)(𝒙𝟐 − 𝟒𝒙 + 𝟏𝟔) b. (𝒙 − 𝟐)(𝒙 − 𝟐) b. (𝒙 + 𝟐)(𝒙𝟐 − 𝟐𝒙 + 𝟒) c. (𝒙 − 𝟓)(𝒙 − 𝟓) c. (𝒙 + 𝟏)(𝒙𝟐 − 𝒙 + 𝟏) d. (𝒙 − 𝟕)(𝒙 − 𝟕) d. (𝒙 + 𝟑)(𝒙𝟐 − 𝟑𝒙 + 𝟗) e. (𝒙 − 𝟏𝟎)(𝒙 − 𝟏𝟎) a. (𝒙 − 𝟒)(𝒙𝟐 + 𝟒𝒙 + 𝟏𝟔) b. (𝒙 − 𝟐)(𝒙𝟐 + 𝟐𝒙 + 𝟒) c. (𝒙 − 𝟏)(𝒙𝟐 + 𝒙 + 𝟏) d. (𝒙 − 𝟑)(𝒙𝟐 + 𝟑𝒙 + 𝟗) NUCC | Secondary II Math 46 Unit 4.4 Special Products Factoring Worksheet Name _______________________________________________ Period ___________ Factor each polynomial completely. 1. 𝒙𝟐 − 𝟏𝟗𝟔 2. 𝒙𝟐 − 𝟏𝟔 3. 𝒙𝟑 + 𝟏𝟐𝟓 4. 𝐱 𝟐 + 𝟏𝟒𝐱 + 𝟒𝟗 5. 𝐱 𝟐 + 𝟑𝟎𝐱 + 𝟐𝟐𝟓 6. 𝐱 𝟐 − 𝟏𝟖𝐱 + 𝟖𝟏 7. 𝐱 𝟐 − 𝟐𝟒𝐱 + 𝟏𝟒𝟒 8. 𝐱 𝟐 + 𝟔𝐱 + 𝟗 9. 𝐱 𝟑 + 𝟏 10. 𝐱 𝟑 − 𝟐𝟏𝟔 11. 𝐱 𝟑 − 𝟐𝟕 12. 𝐱 𝟐 + 𝟏𝟒𝐱 + 𝟒𝟗 13. 𝐱 𝟐 − 𝟐𝟓 14. 𝒙𝟐 − 𝟖𝟏 15. 𝒙𝟑 − 𝟓𝟏𝟐 16. 𝒙𝟐 + 𝒙 + 𝟏 17. 𝒙𝟐 + 𝟒𝒙 + 𝟒 18. 𝒙𝟐 − 𝟐𝟐𝒙 + 𝟏𝟐𝟏 19. 𝒙𝟐 − 𝟏𝟎𝒙 + 𝟐𝟓 20. 𝒙𝟑 + 𝟏𝟎𝟎𝟎 21. 𝟖𝒙𝟑 + 𝟏 22. 𝟐𝟓𝒙𝟐 − 𝟔𝟒 23. 𝒙𝟐 − 𝟏𝟔𝒚𝟐 24. 𝒙𝟑 − 𝒚𝟑 25. 𝒙𝟐 + 𝟖𝒙 + 𝟏𝟔 26. 𝒙𝟐 + 𝟒𝟎𝒙 + 𝟒𝟎𝟎 27. 𝒙𝟐 − 𝟐𝟔𝒙 + 𝟏𝟔𝟗 28. 𝒙𝟐 − 𝟏𝟎𝒙 + 𝟐𝟓 29 𝟔𝟒𝒙𝟑 + 𝟖 30. 𝒙𝟐 − 𝒚𝟐 31. 𝟖𝒙𝟑 − 𝟐𝟕 32. 𝟗𝒙𝟐 − 𝟐𝟓 33. 𝒙𝟒 − 𝟏𝟔 NUCC | Secondary II Math 47 Unit 4.4 34. Given that the area of a square is 𝟑𝟔𝒙𝟐 − 𝟒𝟗, write and expression for square’s length and width? 35. Given that the area of a square is 𝒙𝟐 + 𝟏𝟔𝒙 + 𝟔𝟒, write and expression for square’s length and width? 36. Given that the area of a square is 𝒙𝟐 − 𝟑𝟐𝒙 + 𝟐𝟓𝟔, write and expression for square’s length and width? 37. A company makes square copper tiles with an area of 𝒙𝟐 + 𝟐𝟒𝒙 + 𝟏𝟒𝟒. Write an expression for the perimeter of a tile. 38. A company makes square iron sheets with an area of 𝒙𝟐 + 𝟔𝒙 + 𝟗. Write an expression for the perimeter of the iron sheets. 39. Write your own problem and its solution using special products. NUCC | Secondary II Math 48 Unit 4.4 Special Products and Factoring Task Names in Group _______________________________________________________________ Date ________________________________ 1. Period ___________ As a group multiply out the following binomials. a. Each student will multiply one set of factors and find the product to complete the table. Student Factors Product (x + 2)(x – 2) (x – 5 )(x + 5) (x + 3)(x – 3) (2x + 1)(2x – 1) (3x – 2 )(3x + 2) b. Write 3 observation or patterns that you see regarding the factors and/or their product. Be prepared to share your observations with the class. NUCC | Secondary II Math 49 Unit 4.4 c. Using your observations, factor the product to complete the table. Student Product Factors 𝒙𝟐 − 𝟒𝟗 𝒙𝟐 − 𝟏𝟔 𝒙𝟐 − 𝟏 𝟐𝟓𝒙𝟐 − 𝟔𝟒 𝟒𝒙𝟐 − 𝟏𝟎𝟎 d. Why might this special product be called the difference of 2 squares? e. Using your observations, write a formula for the difference of 2 squares. 2. As a group multiply out the squared binomial. a. Each student will multiply one squared binomial and find the product to complete the table. Student Factors (Squared Binomial) Product (𝒙 + 𝟐)𝟐 (𝒙 + 𝟓)𝟐 (𝒙 + 𝟏)𝟐 (𝟐𝒙 + 𝟑)𝟐 (𝟑𝒙 + 𝟏)𝟐 NUCC | Secondary II Math 50 Unit 4.4 b. Write 3 observation or patterns that you see regarding the factors and/or their product. Be prepared to share your observations with the class. c. Using your observations, factor the product to complete the table. Student Product Factors (squared binomial) 𝒙𝟐 + 𝟔𝒙 + 𝟗 𝒙𝟐 + 𝟖𝒙 + 𝟏𝟔 𝒙𝟐 + 𝟏𝟒𝒙 + 𝟒𝟗 𝟐𝟓𝒙𝟐 + 𝟖𝟎𝒙 + 𝟔𝟒 𝟒𝒙𝟐 + 𝟒𝟎𝒙 + 𝟏𝟎𝟎 d. Why might this special product be called the square of a binomial? e. Using your observations, write a formula for the square of a binomial with a sum. NUCC | Secondary II Math 51 Unit 4.4 3. As a group multiply out the squared binomial. a. Each student will multiply one squared binomial and find the product to complete the table. Student Factors (Squared Binomial) Product (𝒙 − 𝟐)𝟐 (𝒙 − 𝟔)𝟐 (𝒙 − 𝟒)𝟐 (𝟐𝒙 − 𝟑)𝟐 (𝟑𝒙 − 𝟐𝟓)𝟐 b. Write 3 observation or patterns that you see regarding the factors and/or their product. Be prepared to share your observations with the class. c. Using your observations, factor the product to complete the table. Student Product Factors (squared binomial) 𝒙𝟐 − 𝟏𝟎𝒙 + 𝟐𝟓 𝒙𝟐 − 𝟐𝟎𝒙 + 𝟏𝟎𝟎 𝒙𝟐 − 𝟏𝟒𝒙 + 𝟒𝟗 𝟗𝒙𝟐 − 𝟐𝟒𝒙 + 𝟏𝟔 𝟒𝒙𝟐 − 𝟑𝟔𝒙 + 𝟖𝟏 NUCC | Secondary II Math 52 Unit 4.4 d. How is this special product different from the last square of a binomial? e. Using your observations, write a formula for the square of a binomial with a difference. 5. As a group multiply out the factors. Each student will multiply one factor and find the product to complete the table. Student Factors (Cubed Binomial) Product (𝒙 + 𝟐)(𝒙𝟐 − 𝟐𝒙 + 𝟒) (𝒙 + 𝟓)(𝒙𝟐 − 𝟓𝒙 + 𝟐𝟓) (𝒙 + 𝟑)(𝒙𝟐 − 𝟑𝒙 + 𝟗) (𝟐𝒙 + 𝟑)(𝟒𝒙𝟐 − 𝟔𝒙 + 𝟗) (𝟑𝒙 + 𝟏)(𝟗𝒙𝟐 − 𝟑𝒙 + 𝟏) 6. Write 3 observations or patterns that you see regarding the factors and/or their products. Be prepared to share your observations with the class. NUCC | Secondary II Math 53 Unit 4.4 7. Using your observations, factor the product to complete the table. Student Product Factors 𝒙𝟑 + 𝟖 𝒙𝟑 + 𝟔𝟒 𝒙𝟑 + 𝟏𝟎𝟎𝟎 𝟐𝟕𝒙𝟑 + 𝟏𝟐𝟓 𝟔𝟒𝒙𝟑 + 𝟏 8. Using your observations, write a formula for the sum of two cubes. 9. What is a conjugate? Give the definition and 2 examples. Did any of the patterns you discovered above have conjugates? Which ones? NUCC | Secondary II Math 54 Unit 4.4 I Have, Who Has Factoring Worksheet I have x2 – 18x + 81. Who has (x – 10)(x + 1)? I have x2 – 9x – 10. Who has (x + 12)(x – 3)? I have x2 – 9x – 36. Who has (x + 7)(x + 7)? I have x2 + 14x + 49. Who has (x + 2)(x – 6)? I have x2 – 4x – 12. Who has (x + 11)(x – 3)? I have x2 + 8x – 33. Who has (x + 8)(x + 4)? I have x2 + 12x + 32. Who has (x – 15)(x – 4)? I have x2 – 19x + 60. Who has (x – 6)(x + 6)? I have x2 – 36. Who has (x + 2)(x + 7)? I have x2 + 9x + 14. Who has (x + 9)(x – 5)? I have x2 + 4x – 45. Who has (x + 1)(x + 1)? I have x2 + 2x + 1. Who has (x + 9)(x + 9)? I have x2 + 18x + 81. Who has (x + 6)(x – 10)? I have x2 – 4x – 60. Who has (x – 6)(x – 6)? I have x2 – 12x + 36. Who has (x – 15)(x + 4)? I have x2 – 11x – 60. Who has (x + 1)(x + 10)? I have x2 + 11 x + 10. Who has (x – 9)(x – 3)? I have x2 – 12x + 27. Who has (x – 6)(x + 4)? NUCC | Secondary II Math 55 Unit 4.4 I have x2 – 2x – 24. Who has (x – 8)(x – 4)? I have x2 – 12x + 32. Who has (x – 9)(x + 6)? I have x2 – 3x – 54. Who has (x + 15)(x + 4)? I have x2 + 19x + 60. Who has (x + 7)(x + 3)? I have x2 + 10x + 21. Who has (x – 8)(x – 3)? I have x2 – 11x + 24. Who has (x + 5)(x + 9)? I have x2 + 14x + 45. Who has (x – 2)(x – 10)? I have x2 – 12x + 20. Who has (x + 7)(x – 3)? I have x2 + 4x – 21. Who has (x + 9)(x + 6)? I have x2 + 15x + 54. Who has (x – 8)(x – 7)? I have x2 – 15x + 56. Who has (x + 8)(x + 5)? I have x2 + 13x + 40. Who has (x – 6)(x – 10)? I have x2 – 16x + 60. Who has (x + 6)(x + 5)? I have x2 + 11x + 30. Who has (x – 12)(x + 3)? I have x2 – 9x – 36. Who has (x – 1)(x – 1)? I have x2 – 2x + 1. Who has (x + 3)(x + 3)? I have x2 + 6x + 9. Who has (x – 9)(x + 3)? I have x2 – 6x – 27. Who has (x – 7)(x + 3)? NUCC | Secondary II Math 56 Unit 4.4 I have x2 – 4x – 21. Who has (x – 1)(x + 10)? I have x2 + 9x – 10. Who has (x – 6)(x – 5)? I have x2 – 11x + 30. Who has (x – 3)(x – 3)? I have x2 – 6x + 9. Who has (x + 15)(x – 4)? I have x2 + 11x – 60. Who has (x + 5)(x + 7)? I have x2 + 12x + 35. Who has (x + 9)(x – 3)? I have x2+ 6x – 27. Who has (x + 6)(x + 10)? I have x2 + 16x + 60. Who has (x – 11)(x + 2)? I have x2 – 9x – 22. Who has (x – 2)(x – 7)? I have x2 – 9x + 14. Who has (x + 5)(x – 9)? I have x2 – 4x – 45. Who has (x + 9)(x + 3)? I have x2 + 12x + 27. Who has (x – 9)(x – 9)? NUCC | Secondary II Math 57 Unit 4.4 Special Products Bell Quiz Name _______________________________________________ Period ___________ Factor each polynomial. 1. 𝒙𝟐 + 𝟒𝒙 + 𝟑 2. 𝒙𝟐 − 𝒙 − 𝟒𝟐 3. 𝒙𝟐 − 𝟐𝟒𝒙 + 𝟏𝟒𝟒 4. 𝟓𝒙𝟐 + 𝒙 − 𝟑 5. 𝟔𝒙𝟐 + 𝟏𝟏𝒙 − 𝟏𝟎 NUCC | Secondary II Math 58 Unit 4.5 4.5 INTRO TO COMPLEX NUMBERS Teacher Notes Time Frame: Materials Needed: Related Standards: N.CN.1 Know there is a complex number i such that 𝑖 2 = −1, and every complex number has the form 𝑎 + 𝑏𝑖 with a and b real. Launch John and Betty’s Story Read the story of John and Betty up to page 14 where they introduce i. Print out the John and Betty Guided notes page for each student. http://mathforum.org/johnandbetty Answer the following questions as the story is read. Have the students fill out the first section as you go (Answers are in blue): 1. What kind of numbers do John and Betty start out working with? Whole numbers 2. With three people they had to create Fractions? 3. When they needed to find the length of the sides of the square what kind of number was used? Square Roots 4. Why did they create i ? So that it could multiply itself to get a negative number. 5. How is i defined in the story? 𝑖 ∙ 𝑖 = −1 or 𝑖 2 = −1 NUCC | Secondary II Math 59 Unit 4.5 Explore In pairs or small groups of students answer the following questions. 6. Why did they use i? 7. Is i imaginary, like a make believe friend? 8. Think of looking in a mirror. What do you see? a. Is it real? b. Is it imaginary? c. What does the image see when it looks in the mirror? d. Is it real? 9. Answer again, why did they use i? 10. How is i defined in the story? If 𝑖 2 = −1 , what does i equal? 𝑖 = √−1 11. Can you mix real numbers with imaginary numbers? How would you represent real numbers mixed with imaginary numbers? Examples: 6 + 4𝑖; 5 − 3𝑖 Discuss As a class discuss the students’ responses to the questions and the concept of imaginary numbers. 12. Can you mix real numbers with imaginary numbers? How would you represent real numbers mixed with imaginary numbers? Examples: 6 + 4𝑖; 5 − 3𝑖 13. These are called complex numbers. Complex numbers are written in the form 𝑎 + 𝑏𝑖, where a is the _real number_ part and bi is the _imaginary number_ part. Also, a is a _real _ number and the coefficient b is a _real _ number. 14. Properties of taking a square root of a negative number. If r is a positive real number, then √−𝑟 = 𝑖 √𝑟 It follows that (𝑖√𝑟)2 = −𝑟 What are some real world applications to imaginary numbers? http://www.lessonplanet.com/article/math/real-world-applications-to-imaginary-andcomplex-numbers. NUCC | Secondary II Math 60 Unit 4.5 Ready, Set, Go! Complex Numbers Worksheet NUCC | Secondary II Math 61 Unit 4.5 Mathematics Content Cluster Title: Perform arithmetic operations with complex numbers. Standard N.CN.1: Know there is a complex number i such that i2 = -1, and every complex number has the form a + bi with a and b real. Concepts and Skills to Master • • Understand that the set of complex numbers includes the set of all real numbers and the set of imaginary numbers. Express numbers in the form a + bi. Critical Background Knowledge • Real number system and its subsets.. Academic Vocabulary real numbers, complex numbers, imaginary numbers, I, a + bi Suggested Instructional Strategies • Use the definition of square root and the Fundamental Theorem of Algebra to show the need for √−1 . Consider this in Skills: • Write √−25 + √9 as a complex number in the form of a + bi. a historical context. • • Solve x2 – a2 = 0 and x2 + a2 = 0 where a is an integer. Connect imaginary solutions to the graphs of quadratic functions. Some Useful Websites: http://mathforum.org/johnandbetty http://www.lessonplanet.com/article/math/real-world-applications-to-imaginary-and-complexnumbers NUCC | Secondary II Math 62 Unit 4.5 Complex Numbers: Name _______________________________________________ Period ___________ Ready, Set, Go! Ready Prerequisite problems: A. Simplify the expression. 1. √64 2. √28 3. √3 ∙ √27 4. 4√36 B. Solve the equation 5. 𝑠 2 = 169 6. 4𝑝2 = 448 7. 7𝑟 2 − 10 = 25 8. 𝑥 2 = 84 Today’s BIG idea. C. Simplify 7. √−36 8. − √−16 9. 11√−81 10. 16 − √−16 12. 3√−9 13. −2√−16 14. 44 − √−1 16. 𝑥 2 + 11 = 3 17. 3𝑥 2 − 7 = −31 18. 5𝑥 2 + 33 = 3 Set 11. ±√−49 D. Solve the equation 15. 𝑠 2 = −13 E. In each expression identify the real number part a and the imaginary number part bi. 19. 4 − 7𝑖 20. 5 + 4𝑖 21. 15 22. 12𝑖 Go F. Mixed Review 23. State the polynomial in standard form in regard to x: 4𝑥 2 − 8𝑥 + 𝑥 3 𝑦 + 11𝑦 2 24. Factor the polynomial completely: 25. Factor the special product: 26. Find the missing angle: 27. Solve the proportion: 126 𝑘 3𝑥 2 − 2𝑥 − 5 𝑥 2 + 4𝑥 + 4 = 14 3 NUCC | Secondary II Math 63 Unit 4.5 Name _______________________________________________ Period ___________ The Story of John and Betty Guided Notes Answer the following questions as the story is read. 1. What kind of numbers do John and Betty start out working with? 2. With three people they had to create ________? 3. When they needed to find the length of the sides of the square what kind of number was used? 4. Why did they create i? 5. How is i defined in the story? In pairs or small groups discuss and answer the following questions. 6. Why did they use i? 7. Is i imaginary, like a make believe friend? 8. Think of looking in a mirror. What do you see? Is it real? Is it imaginary? What does the image see when it looks in the mirror? Is it real? 9. Answer again, why did they use i ? 10. How is I defined in the story? If i2 = -1; what does i equal? 11. Can you mix real numbers with imaginary numbers? How would you represent real numbers mixed with imaginary numbers? As a class discuss the responses to the questions and the concept of imaginary numbers. 12. Can you mix real numbers with imaginary numbers? How would you represent real numbers mixed with imaginary numbers? (Discuss what you discovered in question 11) 13. These are called ___________________. Complex numbers are written in the form _______ where a is the ________ part and bi is the ___________ part. Also, a is a ______ number and the coefficient b is a ______ number. 14. Properties of taking a square root of a negative number. NUCC | Secondary II Math 64 Unit 4.6 4.6 OPERATIONS WITH COMPLEX NUMBERS Teacher Notes Time Frame: Materials Needed: Related Standards: N.CN.2 Use the relation 𝑖 2 = −1 and the commutative, associative, and distributive properties to add, subtract and multiply complex numbers. Launch List the different number systems. Natural numbers, Integers, Rational and Irrational, Real numbers, Imaginary numbers, Complex numbers. Can you come up with a way to visually organize all these different number systems? (example of one way): Complex Numbers (C) Real Numbers (R) Imaginary Numbers (Im) Could we combine two complex numbers together? What kind of number would you get? Come up with three ways to combine complex numbers. Can you write some examples? Add, subtract, and multiply. Explore Mix –N –Match This activity is done with adding and subtracting complex numbers. Print activity on heavier paper and cut into problems. NUCC | Secondary II Math 65 Unit 4.6 Instructions for the activity. 1. Each student is given a card with a problem to complete. 2. Once the question is answered they mix around the middle of the room until they find a match, another student with the same answer. Once their match is found they move to the outside of the room to discuss. 3. Partners quiz and discuss with each other about how they found the solution. Students coach and praise each other. 4. Students are then given another card or can pass cards so each student has a new problem for another round. Discuss What are the steps you took to add or subtract the complex numbers? Simplify any negative square roots. Commutative and associative properties to combine real number with real number and imaginary number with imaginary number. What kind of numbers did you see in the solutions? Real numbers, imaginary numbers, complex numbers What about multiplying complex numbers? Are there properties that we can review to help with multiplying? Distributive property; FOILing NUCC | Secondary II Math 66 Unit 4.6 Assign Ready, Set, Go! Worksheet NUCC | Secondary II Math 67 Unit 4.6 Mathematics Content Cluster Title: Perform arithmetic operations with complex numbers. Standard N.CN.2: Use the relation i2 = -1 and the commutative, associative, and distributive properties to add, subtract, and multiply complex numbers. Concepts and Skills to Master Add, subtract, and multiply complex numbers. Critical Background Knowledge Definition of i. Combining like terms in polynomials. (II.1.A.APR.1) Academic Vocabulary Complex numbers, i Suggested Instructional Strategies Relate operations with complex numbers to familiar operations with numbers or polynomial expressions. Skills: Perform the following operations and simplify the solutions. (2 + 3i) + (5 – 7i) (3 – 5i)(2 + 4i) √3(√-6 + 4) Some Useful Websites: NUCC | Secondary II Math 68 Unit 4.6 Teacher’s Master of Mix –N –Match 𝟏. (𝟖 − 𝟔𝒊) + (𝟕 + 𝟒𝒊) 2.(𝟐 − 𝟑𝒊) − (𝟔 − 𝟓𝒊) 3.(𝟐𝟑 + 𝟒𝒊) − (𝟐 + 𝟓𝒊) 4.(𝟑 + 𝟒𝒊) + (𝟔 + 𝟕𝒊) 15 − 2𝑖 −4 + 2𝑖 21 − 𝑖 9 + 11𝑖 𝟓. (𝟏𝟐 + 𝟔𝒊) − (−𝟑 + 𝟒𝒊) 6.(−𝟒 + 𝒊) − (𝟑 − 𝒊) 7.(𝟏𝟓 − 𝟑𝒊) + (𝟔 + 𝟐𝒊) 8.(𝟏𝟎 + 𝟒𝒊) − (𝟏 − 𝟕𝒊) 15 − 2𝑖 −4 + 2𝑖 21 − 𝑖 9 + 11𝑖 9.(𝟏𝟔𝟑𝒊) + (𝟒 + 𝟐𝒊) 10.(𝟏𝟖 + 𝟕𝒊) + (−𝟑 + 𝟏𝟔𝒊) 11.(−𝟏𝟐 − 𝟒𝒊) + (−𝟏𝟎 − 𝟑𝒊) 12.(−𝟖 + 𝟑𝒊) + (−𝟕 − 𝟐𝒊) 20 − 𝑖 15 + 23𝑖 −22 − 7𝑖 −15 + 𝑖 13.(𝟏𝟐 + 𝟔𝒊) + (𝟖 − 𝟕𝒊) 14.(𝟓 + 𝟏𝟏𝒊) + (𝟏𝟎 + 𝟏𝟐𝒊) 15.(−𝟏𝟏 − 𝟑𝒊) − (𝟏𝟏 + 𝒊) 16.(𝟑 + 𝟗𝒊) − (𝟏𝟖 + 𝟖𝒊) 20 − 𝑖 15 + 23𝑖 −22 − 7𝑖 −15 + 𝑖 18.(−𝟐 + 𝟓𝒊) + (𝟐 − 𝟏𝟓𝒊) 19.(𝟏𝟒 + 𝟐𝟔𝒊) − (𝟕 + 𝟑𝒊) 20.(𝟐𝟒 + 𝟏𝟔𝒊) − (𝟏𝟓 + 𝟒𝒊) 0 7 + 23𝑖 9 + 12𝑖 17.(−𝟔𝟑 − 𝟏𝟕𝒊) − (𝟐𝟓 − 𝟕𝒊) −19 21.(𝟔 − 𝟕𝒊) − (𝟐𝟓 − 𝟕𝒊) −19 25.(−𝟏𝟒𝟒 + 𝟏𝟐𝒊) − (𝟐𝟒 + 𝟏𝟔𝒊) −120 − 4𝑖 29.(−𝟔𝟎 − 𝟏𝟎𝒊) − (𝟔𝟎 − 𝟔𝒊) −120 − 4𝑖 33.(𝟖 − 𝟏𝟓𝒊) − (𝟏𝟎 − 𝟑𝒊) −2 − 12𝑖 37.(𝟔 − 𝟔𝒊) − (𝟖 + 𝟔𝒊) −2 − 12𝑖 22.(−𝟏𝟐 + 𝟒𝒊) − (−𝟏𝟐 + 𝟒𝒊) 0 26.(𝟏𝟒 − 𝟑𝒊) − (𝟐𝟎 + 𝟐𝒊) −6 − 5𝑖 30.(−𝟒 + 𝟐𝒊) + (−𝟐 − 𝟕𝒊) −6 − 5𝑖 34.(𝟑 + 𝟗𝒊) − (𝟒 + 𝟐𝒊) −1 + 7𝑖 38.(𝟗 + 𝟏𝟏𝒊) − (𝟏𝟎 + 𝟒𝒊) −1 + 7𝑖 23.(𝟐 + 𝟏𝟒𝒊) − (−𝟓 − 𝟗𝒊) 7 + 23𝑖 9 + 12𝑖 27.(−𝟐𝟒 − 𝟔𝒊) − (−𝟐𝟖 + 𝟔𝒊) 4 − 12𝑖 28.(𝟐 + 𝟏𝟓𝒊) + (𝟏𝟖 + 𝟒𝒊) 20 + 19𝑖 31.(𝟗 − 𝟖𝒊) − (𝟓 + 𝟒𝒊) 4 − 12𝑖 32.(𝟏𝟔 + 𝟕𝒊) + (𝟒 + 𝟏𝟐𝒊) 20 + 19𝑖 35.(𝟏𝟕 − 𝟐𝒊) + (−𝟓 + 𝟕𝒊) 12 + 5𝑖 36.(𝟔 − 𝟓𝒊) + (𝟒 + 𝟐𝒊) 10 − 3𝑖 39.(𝟕 + 𝒊) + (𝟓 + 𝟒𝒊) 12 + 5𝑖 24.(𝟔 + 𝟏𝟒𝒊) − (−𝟑 + 𝟐𝒊) 40.(𝟏𝟕 − 𝟏𝟐𝒊) − (𝟕 + 𝟏𝟓𝒊) 10 − 3𝑖 NUCC | Secondary II Math 69 Unit 4.6 Student copy of Mix –N –Match 𝟏. (𝟖 − 𝟔𝒊) + (𝟕 + 𝟒𝒊) 2.(𝟐 − 𝟑𝒊) − (𝟔 − 𝟓𝒊) 3.(𝟐𝟑 + 𝟒𝒊) − (𝟐 + 𝟓𝒊) 4.(𝟑 + 𝟒𝒊) + (𝟔 + 𝟕𝒊) 𝟓. (𝟏𝟐 + 𝟔𝒊) − (−𝟑 + 𝟒𝒊) 6.(−𝟒 + 𝒊) − (𝟑 − 𝒊) 7.(𝟏𝟓 − 𝟑𝒊) + (𝟔 + 𝟐𝒊) 8.(𝟏𝟎 + 𝟒𝒊) − (𝟏 − 𝟕𝒊) 9.(𝟏𝟔𝟑𝒊) + (𝟒 + 𝟐𝒊) 10.(𝟏𝟖 + 𝟕𝒊) + (−𝟑 + 𝟏𝟔𝒊) 11.(−𝟏𝟐 − 𝟒𝒊) + (−𝟏𝟎 − 𝟑𝒊) 12.(−𝟖 + 𝟑𝒊) + (−𝟕 − 𝟐𝒊) 13.(𝟏𝟐 + 𝟔𝒊) + (𝟖 − 𝟕𝒊) 14.(𝟓 + 𝟏𝟏𝒊) + (𝟏𝟎 + 𝟏𝟐𝒊) 15.(−𝟏𝟏 − 𝟑𝒊) − (𝟏𝟏 + 𝒊) 16.(𝟑 + 𝟗𝒊) − (𝟏𝟖 + 𝟖𝒊) 17.(−𝟔𝟑 − 𝟏𝟕𝒊) − (𝟐𝟓 − 𝟕𝒊) 18.(−𝟐 + 𝟓𝒊) + (𝟐 − 𝟏𝟓𝒊) 19.(𝟏𝟒 + 𝟐𝟔𝒊) − (𝟕 + 𝟑𝒊) 20.(𝟐𝟒 + 𝟏𝟔𝒊) − (𝟏𝟓 + 𝟒𝒊) 21.(𝟔 − 𝟕𝒊) − (𝟐𝟓 − 𝟕𝒊) 22.(−𝟏𝟐 + 𝟒𝒊) − (−𝟏𝟐 + 𝟒𝒊) 23.(𝟐 + 𝟏𝟒𝒊) − (−𝟓 − 𝟗𝒊) 24.(𝟔 + 𝟏𝟒𝒊) − (−𝟑 + 𝟐𝒊) 25.(−𝟏𝟒𝟒 + 𝟏𝟐𝒊) − (𝟐𝟒 + 𝟏𝟔𝒊) 26.(𝟏𝟒 − 𝟑𝒊) − (𝟐𝟎 + 𝟐𝒊) 27.(−𝟐𝟒 − 𝟔𝒊) − (−𝟐𝟖 + 𝟔𝒊) 28.(𝟐 + 𝟏𝟓𝒊) + (𝟏𝟖 + 𝟒𝒊) 29.(−𝟔𝟎 − 𝟏𝟎𝒊) − (𝟔𝟎 − 𝟔𝒊) 30.(−𝟒 + 𝟐𝒊) + (−𝟐 − 𝟕𝒊) 31.(𝟗 − 𝟖𝒊) − (𝟓 + 𝟒𝒊) 32.(𝟏𝟔 + 𝟕𝒊) + (𝟒 + 𝟏𝟐𝒊) 33.(𝟖 − 𝟏𝟓𝒊) − (𝟏𝟎 − 𝟑𝒊) 34.(𝟑 + 𝟗𝒊) − (𝟒 + 𝟐𝒊) 35.(𝟏𝟕 − 𝟐𝒊) + (−𝟓 + 𝟕𝒊) 36.(𝟔 − 𝟓𝒊) + (𝟒 + 𝟐𝒊) 37.(𝟔 − 𝟔𝒊) − (𝟖 + 𝟔𝒊) 38.(𝟗 + 𝟏𝟏𝒊) − (𝟏𝟎 + 𝟒𝒊) 39.(𝟕 + 𝒊) + (𝟓 + 𝟒𝒊) 40.(𝟏𝟕 − 𝟏𝟐𝒊) − (𝟕 + 𝟏𝟓𝒊) NUCC | Secondary II Math 70 Unit 4.6 Name _______________________________________________ Period ___________ Ready, Set, Go! Ready Prerequisite problems: (commutative, associative, distributive properties) A. Identify the property that the statement illustrates. 1. (4 + 9) + 3 = 4 + (9 + 3) B. 2. 7(2 + 8) = 7(2) + 7(8) 3.(12𝑏 + 15) − 3𝑏 = 15 + 9𝑏 Find the product. 4. 𝑖 ∙ 𝑖 5. (𝑥 + 6)(𝑥 + 3) 6. (𝑥 − 5)2 7. 4(𝑥 + 5)(𝑥 − 5) Set Today’s BIG idea. C. Write the expression as a complex number in standard form. 8. (6 − 3𝑖) + (5 + 4𝑖) 9. (9 + 8𝑖) + (8 − 9𝑖) 10. (−2 − 6𝑖) − (4 − 6𝑖) 11. (−1 + 𝑖) − (7 − 5𝑖) 12. (8 + 20𝑖) − (−8 + 12𝑖) 13. (−1 + 4𝑖) + (−9 − 2𝑖) 14. 6𝑖(3 + 2𝑖) 15. −𝑖(4 − 8𝑖) 16. (−2 + 5𝑖)(−1 + 4𝑖) 17. (−1 − 5𝑖)(−1 + 5𝑖) 18. (8 − 3𝑖)(8 + 3𝑖) Go Challenge D. Write the expression as a complex number in standard form. 19. −8 − (3 + 2𝑖) − (9 − 4𝑖) 20. (3 + 2𝑖) + (5 − 𝑖) + 6𝑖 21. 5𝑖(3 + 2𝑖)(8 + 3𝑖) 22. (1 − 9𝑖)(1 − 4𝑖)(4 − 3𝑖) NUCC | Secondary II Math 71 Unit H4.7 H4.7 FACTORING WITH COMPLEX NUMBERS Teacher Notes Time Frame: Materials Needed: Related Standards: N.CN.H.8 Extend polynomial identities to the complex numbers. For example, rewrite 𝑥 2 + 4 as (𝑥 + 2𝑖)(𝑥 − 2𝑖). Launch What are some polynomial identities? When we multiply or factor a polynomial, we see the same patterns over and over again. As learned in 4.4: Difference of Two Squares Perfect Square Sums Perfect Square Differences Sum of Two Cubes Difference of Two Cubes These same patterns are also true when we deal with complex numbers. What pattern helped us to factor a different of squares? For example 𝑥 2 − 9 𝑥 2 − 9 = (𝑥 + 3)(𝑥 − 3) What if we try to factor 𝑥 2 + 9? Explore First consider multiplying these two complex numbers: (𝑥 + 𝑖)(𝑥 − 𝑖) Remember that 𝑖 ∙ 𝑖 = −1 and use the FOIL method to multiply. (𝑥 + 𝑖)(𝑥 − 𝑖) = 𝑥 2 − 𝑥𝑖 + 𝑥𝑖 − 𝑖 2 = 𝑥 2 − (−1) = 𝑥 2 + 1 Now try (𝑥 + 3𝑖)(𝑥 − 3𝑖). (𝑥 + 3𝑖)(𝑥 − 3𝑖) = 𝑥 2 − 3𝑥𝑖 + 3𝑥𝑖 − 9𝑖 2 = 𝑥 2 − 9(−1) = 𝑥 2 + 9 What pattern are you seeing? Based on this pattern could you factor other Sum of two squares polynomials? How would you factor 𝑥 2 + 25? Check your answer. 𝑥 2 + 25 = (𝑥 + 5𝑖)(𝑥 − 5𝑖) Check: (𝑥 + 5𝑖)(𝑥 − 5𝑖) = 𝑥 2 + 5𝑥𝑖 − 5𝑥𝑖 − 25𝑖 2 = 𝑥 2 − 25(−1) = 𝑥 2 + 25 Try 9𝑥 2 + 64. Is this a sum of two squares? Yes (3𝑥)2 + 82 NUCC | Secondary II Math 72 Unit H4.7 What is the imaginary part going to be for each factor? 8𝑖 What are the factors for this sum of two squares? (3𝑥 + 8𝑖)(3𝑥 − 8𝑖) Discuss Remember it is not possible to factor the sum of two squares over real numbers. You can factor the difference of two squares over real numbers. The sum of two squares must be factored over complex numbers. Assign Ready, Set, Go! NUCC | Secondary II Math 73 Unit H4.7 Mathematics Content Cluster Title: Use complex numbers in polynomial identities and equations. Standard N.CN.H.8: Extend polynomial identities to the complex number. (For example, rewrite 𝑥 2 + 4 as (𝑥 + 2𝑖)(𝑥 − 2𝑖).) Concepts and Skills to Master Express a quadratic as a product of two complex factors. Critical Background Knowledge Factor quadratics. Understand that some quadratic functions have complex solutions. Know the definition of i. Perform operations on complex numbers. Standard form of a complex number. Academic Vocabulary conjugates, complex numbers, i, factor Suggested Instructional Strategies Skills: Demonstrate that any binomial quadratic Factor over the complex number system. expression can be expressed as the x2 - 16 Answer: (x + 4i)(x-4i) 2 2 2 difference of two squares (e.g., x + 16 = x x -10x + 34 Answer (x + 5i)(x-5i) – 16i2). Some Useful Websites: NUCC | Secondary II Math 74 Unit H4.7 Name _______________________________________________ Period ___________ Ready, Set, Go! Ready Prerequisites A. Factor the expression 1. 𝑥 2 − 36 2. 4𝑏 2 − 81 3. 36𝑛2 − 9 4. 5𝑥 2 − 45 5. 𝑥 3 − 3𝑥 2 − 16𝑥 + 48 6. 2𝑥 3 − 7𝑥 2 − 8𝑥 + 28 Set B. Factor the polynomial completely 7. 𝑥 2 + 36 8. 𝑥 2 + 100 9. 𝑥 4 − 16 10. 𝑥 3 + 4𝑥 11. 25𝑥 2 + 49 12. 16𝑥 2 − 25 13. 121𝑥 2 − 36𝑦 2 14. 𝑥 3 + 2𝑥 2 + 𝑥 + 2 15. 𝑥 3 − 2𝑥 2 + 16𝑥 − 32 Go Mixed Review C. Simplify each expression 16. ±√−49 17. −√−16 18. 11√−81 D. Find the error in the student’s work 19. 14 − √−16 14 + √16 14 + 4 18 NUCC | Secondary II Math 75 Unit 4 Practice Exam Secondary II Unit 4 Name _______________________ Hour _____ 1. Write the polynomial in standard form and state the degree. 4𝑥 3 − 3𝑥 2 + 𝑥 5 + 5𝑥 7 − 9 2. Write an English statement for the algebraic expression. (3𝑥)2 + 𝑥 Simplify the expression 3. 3𝑦 2 + 5𝑥 − 12𝑥 + 9𝑦 2 − 5 4. 2(𝑥 + 4)(𝑥 − 1) 5. (5𝑥 2 − 7𝑥 + 2) ÷ (𝑥 − 1) Factor the expression completely 6. 𝑎2 − 13𝑎 + 22 7. 12𝑥 2 − 4𝑥 − 40 8. 12𝑚2 − 36𝑚 + 27 Factor the special product expression 9. 4𝑟 2 − 25 10. 25𝑡 2 − 30𝑡 + 9 NUCC | Secondary II Math 76 Unit 4 11. 32𝑣 2 − 2 12. 27𝑚3 + 1 13. −5𝑧 3 + 320 Write the expression as a complex number in standard form 14. (−2 − 6𝑖) − (4 − √−36) 15. (8 − 5𝑖) − (−11 + 4𝑖) 16. 6𝑖(3 + 2𝑖) 17. (5 − 7𝑖)(−1 − 3𝑖) Factor the polynomial completely 18. 4𝑥 2 + 25 19. 3𝑥 2 + 48 20. 𝑥 3 + 2𝑥 2 + 4𝑥 + 8 NUCC | Secondary II Math 77 Unit 4 Exam Secondary II Unit 4 Name _____________________Hour________ 1. Write the polynomial in standard form and state the degree. 𝑥 6 + 6𝑥 2 − 4𝑥 3 + 7 2. Write and English statement for the algebraic expression. 2𝑦 2 3 +𝑦 Simplify the expression 3. 7𝑥 2 + 8 − 3𝑥 − 5𝑥 2 4. 𝑥(2𝑥 + 1)(𝑥 − 3) 5. (4𝑥 2 − 12𝑥 + 5) ÷ (2𝑥 − 1) Factor the expression completely 6. 𝑥 2 + 8𝑥 − 65 7. 20𝑥 2 + 124𝑥 + 24 8. −8𝑦 2 + 28𝑦 − 60 Factor the special product expression 9. 49𝑥 2 − 16 10. 12𝑚2 − 36𝑚 + 27 11. 36𝑥 2 − 84𝑥 + 49 NUCC | Secondary II Math 78 Unit 4 12. 27𝑎3 − 1000 13. 8𝑐 3 + 343 Write the expression as a complex number in standard form. 14. (−1 + √−1) − (7 − √−25) 15. (14 + 3𝑖) + (7 + 6𝑖) 16. −𝑖(4 − 8𝑖) 17. (5 − 7𝑖)(−4 − 3𝑖) Factor the polynomial completely 18. 16𝑥 2 + 49 19. 8𝑥 2 + 50 20. 9𝑥 3 + 27𝑥 2 + 16𝑥 + 48 NUCC | Secondary II Math 79