Polynomial Functions Unit Learning Targets Students will be able to identify independent and dependent variables and domain and range in polynomial situations, as well as model the situations with tables, graphs, and rules, and describe the pattern in the table (both the pattern and the number that shows up). Students will be able to identify the degree of a polynomial in both factored and simplified form, and use it to identify the potential number of local max/mins, xintercepts, and number of possible solutions, as well as describe the general shape and end behavior of a polynomial’s growth (in combination with the leading coefficient). Students will be able to find the x-intercepts given any polynomial rule in factored form, as well as distribute rules into simplified form. Students will be able to write a polynomial rule in factored form given a degree ‘n’ and the x-intercepts. Students will be able to write out the calculation steps for a given rule, write the inverse rule or identify when the inverse rule is not possible, and invert and solve root functions. Title of Unit Curriculum Area Developed By Polynomial Functions Algebra Grade Level Time Frame 10th Grade Approximately 10 assignments, approximately 4-6 weeks Isaac Frank Identify Desired Results (Stage 1) Content Standards High School: Algebra SSE.A.1.A: Interpret parts of an expression, such as terms, factors, and coefficients. SSE.A.2: Use the structure of an expression to identify ways to rewrite it. SSE.B.3: Choose and produce an equivalent form of an expression to reveal and explain properties of the quantity represented by the expression. APR.B.3: Identify zeros of polynomials when suitable factorizations are available, and use the zeros to construct a rough graph of the function defined by the polynomial. CED.A.1: Create equations and inequalities in one variable and use them to solve problems. High School: Functions IF.A.1: Use function notation, evaluate functions for inputs in their domains, and interpret statements that use function notation in terms of context. IF.B.1: For a function that models a relationship between two quantities, interpret key features of graphs and tables in terms of the quantities, and sketch graphs showing key features given a verbal description of the relationship. IF.C.7: Graph functions expressed symbolically and show key features of the graph, by hand in simple cases and using technology for more complicated cases. IF.C.7.A: Graph linear and quadratic functions and show intercepts, maxima, and minima. IF.C.7.C: Graph polynomial functions, identifying zeros when suitable factorizations are available, and showing end behavior. IF.C.8: Write a function defined by an expression in different but equivalent forms to reveal and explain different properties of the function. BF.A.1: Write a function that describes a relationship between two quantities. BF.B.4: Find inverse functions. BF.B.4.A: Solve an equation of the form f(x)=c for a simple function f that has an inverse and write an expression for the inverse. Standards for Mathematical Practice CCSS.MATH.PRACTICE.MP1: Make sense of problems and persevere in solving them. CCSS.MATH.PRACTICE.MP2: Reason abstractly and quantitatively. CCSS.MATH.PRACTICE.MP3: Construct viable arguments and critique the reasoning of others. CCSS.MATH.PRACTICE.MP4: Model with mathematics. CCSS.MATH.PRACTICE.MP6: Attend to precision. CCSS.MATH.PRACTICE.MP7: Look for and make use of structure. CCSS.MATH.PRACTICE.MP8: Look for and express regularity in repeated reasoning. Understandings Overarching Understanding Students will understand how the coefficients and constants in a polynomial rule (in factored form, primarily) affect the graph of the rule Students will understand when an inverse can be found for a polynomial and when one cannot be found Students will understand how to describe what a graph looks like based on the factored form of the rule Students will understand how the degree of the polynomial rule affects the graph and table Essential Questions Overarching What does the graph of this polynomial look like? What is causing it to look that way? How can I solve this polynomial? What is the domain/range of this function? What is the end behavior of this function? Topical How many local max/mins are there/can there be? How many x-intercepts are there/can there be? Why can/can’t we find the invers of this function? What numbers need to go in the rest of the rule to fulfill the given criteria? Related Misconceptions Students may just apply the math from quadratics to polynomials with higher degrees without realizing that different math may apply. Students may also try to use the process we used to get quadratics into vertex form and end up turning a different degree polynomial into a quadratic. Objectives Skills Knowledge Students will know… Students will be able to… How the coefficients/constants in a rule affect the graphs and tables of polynomial How to identify the degree of a polynomial How to simplify polynomial rules When and how to inverse polynomial rules When it is and is not possible to invert polynomial rules Model a cubic situation Describe patterns, relationships, and characteristics of tables and graphs of polynomials Simplify polynomial rules Create polynomial rules to fulfill given criteria Identify the domain and range of polynomial functions Solve polynomial equations using the inverse (when possible) Recognize when it is not possible to invert a polynomial equation and explain why Assessment Evidence (Stage 2) Performance Task Description Goal Role Audience Situation Product/Performance Standards Assess the students’: ability to identify the x- and y-intercepts based on a rule in factored form; understanding of the degree of polynomials; comprehension of end behavior of polynomials; ability to sketch a graph based on a rule; understanding of when and it is possible/impossible to find an inverse of a polynomial; understanding of the coefficients in a polynomial rule, and how they affect the graph and table of the rule; ability to write a rule that satisfies given criteria; ability to solve a polynomial using the inverse; ability to simplify a polynomial; understanding of domain and range of a polynomial End of unit test Myself, Craig Huhn (mentor teacher) Summative unit exam (taken during regular class period) Test SSE.A.1.A: Interpret parts of an expression, such as terms, factors, and coefficients. SSE.A.2: Use the structure of an expression to identify ways to rewrite it. SSE.B.3: Choose and produce an equivalent form of an expression to reveal and explain properties of the quantity represented by the expression. CED.A.1: Create equations and inequalities in one variable and use them to solve problems. IF.B.1: For a function that models a relationship between two quantities, interpret key features of graphs and tables in terms of the quantities, and sketch graphs showing key features given a verbal description of the relationship. IF.C.8: Write a function defined by an expression in different but equivalent forms to reveal and explain different properties of the function. BF.B.4: Find inverse functions. BF.B.4.A: Solve an equation of the form f(x)=c for a simple function f that has an inverse and write an expression for the inverse. Other Evidence Learning Plan (Stage 3) Concept in Unit Properties of Cubing Lesson Topic Lesson Learning Objective Introducing cubing using volume SWBAT model a cubic situation (volume) Properties of cubic functions SWBAT describe patterns, relationships, and characteristics of the tables and graphs of (two) cubic functions. Properties of cubic functions SWBAT describe patterns, relationships, and characteristics cubic functions Simplifying/creating Simplifying rules polynomial rules Creating polynomial rules SWBAT simplify polynomial rules SWBAT create polynomial rules that fulfill given criteria Description of how lesson contributes to unit-level objectives This lesson has students modeling a cubic situation by making boxes with different dimensions using regular sheets of copier paper. This lesson has students evaluating three linear rules and their combined cubic product for multiple x values, making tables and graphs of the equations, simplifying the cubic rule, and comparing significant features of linears and cubics. This lesson has students recapping the properties and characteristics of cubic functions, and building the understanding of important features. This lesson has simplifying polynomial rules of degree 3, 4, 5, and 6. This lesson has students create rules with given characteristics (or explain why it is not possible), as well as complete rules in factored form so that they fulfill given requirements. Assessment activities Assignment (Making Rectangular Containers), small group work, class discussion on assignment Table, graph, Writing a rule Assignment (Product of Three Lines), small group work, class discussion on assignment Table, graph, descriptions of patterns in both Simplified rules Assignment (Cubic Functions Recap), small group work, class discussion on assignment Descriptions of properties and functions Assignment (Simplifying Rules), small group work, class discussion on assignment Simplified rules Assignment (Making Polynomial Rules), small group work, class discussion on assignment Created rules Characteristics of polynomials X-intercepts of polynomials SWBAT describe the tables and graphs of polynomial functions based on rules in factored form This lesson has students describe the characteristics of tables of graphs of polynomials of degree 3 4, and 5. Assignment (Focus on x-intercepts), small group work, class discussion on assignment Descriptions of characteristics Domain and Range of polynomials SWBAT identify the domain and range of polynomial functions This lesson has students both giving examples of functions with a given domain or range, as well as giving the domain or range of given functions. Assignment (Domain and Range), small group work, class discussion on assignment Solving Polynomials Inverses of Polynomials Practice Test These lessons have students find the inverses of polynomial rules (if possible) and use them to solve, as well as recognize when it is not possible to invert and explain why. This lesson gives students the opportunity to practice taking the unit test, with a day to review it with their peers the next day, with the real test the day after the review. Assignments (Using Inverses to Solve Polynomials; Solving Practice), small group work, class discussion on assignment Practice Test SWBAT solve polynomial equations using the inverse, or recognize when that is not possible SWBAT demonstrate their knowledge of the unit Assignment (Polynomials Practice Test), small group work (day after) Test Both Craig and I will assess much of the evidence of student learning in day-to-day interactions and conversations with students, as well as class discussions. We will also use warm-ups to quickly check where students are at with their understanding of learning targets, as well as possible giving one or two quizzes. At the end of the unit, students will also get credit for the day-to-day work they have been doing on the tasks we have handed out by handing in their unit packet. Polynomial Functions Unit Test Name ________________________ Make sure to show all of your work and explain completely. Answer every question, and be sure not to spend too much time on one problem. Feel free to skip around, but make sure you attempt all problems. If you get done before the time is up, use your calculator to verify or check your answers. Answer the following questions about f(x) = -7(x – 5)(x + 2)(x – 1.3)(x – 100)(x + 4). 1) a. Identify the x-intercepts, and explain how you knew what they were without searching in the table. b. Identify the y-intercept and explain how you got it. c. What degree is this polynomial, and how do you know? d. What does the right end of this graph look/behave like? How do you know based just on the rule? e. What does the left end of this graph look/behave like? How do you know this based just on the rule? Answer the following questions still about f(x) = -7(x – 5)(x + 2)(x – 1.3)(x – 100)(x + 4). f. Sketch a graph with the maximum number of “bumps” for this function (and the correct end behavior). How do you know each of these properties from the rule? g. Can you find the inverse rule for this function? If so, how would you do it; if not, why not? 2) What would have to be true about the leading coefficient (the a value) and the degree of the polynomial to make a graph like this? For each, say how you know. 3) Describe the pattern in the table for –5x3 + 4x2 – 8x + 9, without having to make the table and check. Full credit will be given if the pattern and the number is given. 4) Write a rule for a polynomial of degree four with the x-intercepts of only (2,0) , (-4,0) and (1.5,0). 5) Solve the following using inverses. If it cannot be done without searching, say so and why this is the case. ( x 3) = -300 6 5 a. 7x – 9 = 0 c. 5( x 4) 3 10 0 d. e. 4 x 6 7 22 f. 2 b. 12 x 4 11x 3 10 7.875 11( x 3) 4 9 4 6) Simplify (-2x + 8)(x – 6)(4x + 1). 7) What is the maximum number of zeroes that could result in a 10th degree polynomial? 8) Define the domain and range of the following function: f(x) = -3x4 – 4x2 + 5x - 4 EXTRA CREDIT: Given the polynomial f(x) = px3 + 12x2+ q , find values for p and q that give a polynomial with all positive outputs. Explain why your chosen values of p and q give positive outputs or why the task is not possible.