On a blank piece of paper please complete PG 328 complete #1-12 on the Prerequisite Skills Chapter 5: Polynomials & Polynomial Functions BIG IDEAS: 1. Performing operations with polynomials 2. Solving polynomial equations and finding zeros Lesson 1: Use Properties of Exponents ESSENTIAL QUESTION How do you simplify algebraic expressions with exponents? VOCABULARY • Scientific notation: The representat5ion of a number in the form c x 10n where 1≤c<10 and n is an integer. EXAMPLE 1 a. Evaluate numerical expressions (–4 25)2 = (– 4)2 (25)2 Power of a product property = 16 25 2 Power of a power property = 16 210 b. 115 118 –1 = 16,384 Simplify and evaluate power. 118 = 115 Negative exponent property = 118 – 5 Quotient of powers property = 113 = 1331 Simplify and evaluate power. EXAMPLE 3 a. b. Simplify expressions b–4b6b7 r–2 s3 = b–4 + 6 + 7 –3 ( r –2 )–3 = ( s3 )–3 = c. 16m4n –5 2n–5 r6 s–9 = b9 Product of powers property Power of a quotient property Power of a power property = r6s9 Negative exponent property = 8m4n –5 – (–5) Quotient of powers property = 8m4n0= 8m4 Zero exponent property EXAMPLE 4 Standardized Test Practice SOLUTION (x–3y3)2 x5y6 = = (x–3)2(y3)2 x5y6 x –6y6 x5y6 Power of a product property Power of a power property GUIDED PRACTICE for Examples 3, 4, and 5 Simplify the expression. Tell which properties of exponents you used. 5. x–6x5 x3 ANSWER 6. x2 ; Product of powers property (7y2z5)(y–4z–1) ANSWER 7z4 y2 ; Product of powers property, Negative exponent property for Examples 3, 4, and 5 GUIDED PRACTICE 7. s3 2 t–4 ANSWER 8. x4y–2 s6t8 ; Power of a power property, Negative exponent property 3 x3y6 x3 ANSWER y24 ; Quotient of powers property, Power of a Quotient property, Negative exponent property ESSENTIAL QUESTION How do you simplify algebraic expressions with exponents. Use the properties of exponents to rewrite it with only positive exponents Simplify the expression (-3x3) (5x) Lesson 3: Add, Subtract and Multiply Polynomials ESSENTIAL QUESTION What are the special product patterns? VOCABULARY • Like Terms: Terms that have the same variable parts. Constant terms are also like terms. EXAMPLE 1 Add polynomials vertically and horizontally a. Add 2x3 – 5x2 + 3x – 9 and x3 + 6x2 + 11 in a vertical format. SOLUTION a. 2x3 – 5x2 + 3x – 9 + x3 + 6x2 + 11 3x3 + x2 + 3x + 2 EXAMPLE 1 Add polynomials vertically and horizontally b. Add 3y3 – 2y2 – 7y and –4y2 + 2y – 5 in a horizontal format. (3y3 – 2y2 – 7y) + (–4y2 + 2y – 5) = 3y3 – 2y2 – 4y2 – 7y + 2y – 5 = 3y3 – 6y2 – 5y – 5 EXAMPLE 2 Subtract polynomials vertically and horizontally a. Subtract 3x3 + 2x2 – x + 7 from 8x3 – x2 – 5x + 1 in a vertical format. SOLUTION a. Align like terms, then add the opposite of the subtracted polynomial. 8x3 – x2 – 5x + 1 – (3x3 + 2x2 – x + 7) 8x3 – x2 – 5x + 1 + – 3x3 – 2x2 + x – 7 5x3 – 3x2 – 4x – 6 EXAMPLE 2 Subtract polynomials vertically and horizontally b. Subtract 5z2 – z + 3 from 4z2 + 9z – 12 in a horizontal format. Write the opposite of the subtracted polynomial, then add like terms. (4z2 + 9z – 12) – (5z2 – z + 3) = 4z2 + 9z – 12 – 5z2 + z – 3 = 4z2 – 5z2 + 9z + z – 12 – 3 = –z2 + 10z – 15 for Examples 1 and 2 GUIDED PRACTICE Find the sum or difference. 1. (t2 – 6t + 2) + (5t2 – t – 8) ANSWER 6t2 – 7t – 6 2. (8d – 3 + 9d3) – (d3 – 13d2 – 4) ANSWER 8d3 + 13d2 + 8d + 1 EXAMPLE 3 Multiply polynomials vertically and horizontally a. Multiply –2y2 + 3y – 6 and y – 2 in a vertical format. b. Multiply x + 3 and 3x2 – 2x + 4 in a horizontal format. SOLUTION a. –2y2+ 3y – 6 y –2 4y2 – 6y + 12 Multiply –2y2 + 3y – 6 by –2 . –2y3 + 3y2 – 6y Multiply –2y2 + 3y – 6 by y –2y3 + 7y2 –12y + 12 Combine like terms. EXAMPLE 3 Multiply polynomials vertically and horizontally b. (x + 3)(3x2 – 2x + 4) = (x + 3)3x2 – (x + 3)2x + (x + 3)4 = 3x3 + 9x2 – 2x2 – 6x + 4x + 12 = 3x3 + 7x2 – 2x + 12 EXAMPLE 4 Multiply three binomials Multiply x – 5, x + 1, and x + 3 in a horizontal format. (x – 5)(x + 1)(x + 3) = (x2 – 4x – 5)(x + 3) = (x2 – 4x – 5)x + (x2 – 4x – 5)3 = x3 – 4x2 – 5x + 3x2 – 12x – 15 = x3 – x2 – 17x – 15 EXAMPLE 5 Use special product patterns a. (3t + 4)(3t – 4) = (3t)2 – 42 Sum and difference = 9t2 – 16 b. (8x – 3)2 = (8x)2 – 2(8x)(3) + 32 Square of a binomial = 64x2 – 48x + 9 c. (pq + 5)3 = (pq)3 + 3(pq)2(5) + 3(pq)(5)2 + 53 = p3q3 + 15p2q2 + 75pq + 125 Cube of a binomial for Examples 3, 4 and 5 GUIDED PRACTICE Find the product. 3. (x + 2)(3x2 – x – 5) ANSWER 3x3 + 5x2 – 7x – 10 4. (a – 5)(a + 2)(a + 6) ANSWER (a3 + 3a2 – 28a – 60) 5. (xy – 4)3 ANSWER x3y3 – 12x2y2 + 48xy – 64 ESSENTIAL QUESTION What are the special product patterns? (a+b)(a-b) = a2 – b2 (a+b)2= a2 + 2ab + b2 (a-b)2= a2 - 2ab + b2 (a+b)3= a3 + 3a2b + 3ab2 + b3 (a-b)3= a3 - 3a2b + 3ab2 - b3 Multiply the polynomials: a) (x+2) (x+3) b) (2x – 1) (2x + 1) Lesson 4: Factor and Solve Polynomial Equations ESSENTIAL QUESTION How can you solve a higher-degree polynomial equation? VOCABULARY • Factored Completely: A factorable polynomial with integer coefficients is factored completely if it is written as a product of un-factorable polynomials with integer coefficients • Factor by grouping: To factor a polynomial with four terms by grouping, factor common monomials from pairs of terms, then look for a common binomial factor • Quadratic Form: The form au2 + bu + c, where u is any expression in x. EXAMPLE 1 Find a common monomial factor Factor the polynomial completely. a. b. c. x3 + 2x2 – 15x 2y5 – 18y3 = x(x2 + 2x – 15) Factor common monomial. = x(x + 5)(x – 3) Factor trinomial. = 2y3(y2 – 9) Factor common monomial. = 2y3(y + 3)(y – 3) Difference of two squares 4z4 – 16z3 + 16z2 = 4z2(z2 – 4z + 4) Factor common monomial. = 4z2(z – 2)2 Perfect square trinomial EXAMPLE 2 Factor the sum or difference of two cubes Factor the polynomial completely. a. x3 + 64 = x3 + 43 Sum of two cubes = (x + 4)(x2 – 4x + 16) b. 16z5 – 250z2 = 2z2(8z3 – 125) Factor common monomial. = 2z2 (2z)3 – 53 Difference of two cubes = 2z2(2z – 5)(4z2 + 10z + 25) GUIDED PRACTICE for Examples 1 and 2 Factor the polynomial completely. 1. x3 – 7x2 + 10x ANSWER 2. 3y5 – 75y3 ANSWER 3. 3y3(y – 5)(y + 5 ) 16b5 + 686b2 ANSWER 4. x( x – 5 )( x – 2 ) 2b2(2b + 7)(4b2 –14b + 49) w3 – 27 ANSWER (w – 3)(w2 + 3w + 9) EXAMPLE 3 Factor by grouping Factor the polynomial x3 – 3x2 – 16x + 48 completely. x3 – 3x2 – 16x + 48 = x2(x – 3) – 16(x – 3) Factor by grouping. = (x2 – 16)(x – 3) Distributive property = (x + 4)(x – 4)(x – 3) Difference of two squares EXAMPLE 4 Factor polynomials in quadratic form Factor completely: (a) 16x4 – 81 and (b) 2p8 + 10p5 + 12p2. a. 16x4 – 81 = (4x2)2 – 92 Write as difference of two squares. = (4x2 + 9)(4x2 – 9) Difference of two squares = (4x2 + 9)(2x + 3)(2x – 3) Difference of two squares b. 2p8 + 10p5 + 12p2 = 2p2(p6 + 5p3 + 6) Factor common monomial. = 2p2(p3 + 3)(p3 + 2) Factor trinomial in quadratic form. GUIDED PRACTICE for Examples 3 and 4 Factor the polynomial completely. 5. x3 + 7x2 – 9x – 63 ANSWER 6. 16g4 – 625 ANSWER 7. (x + 3)(x – 3)(x + 7) (4g2 + 25)(2g + 5)(2g – 5) 4t6 – 20t4 + 24t2 ANSWER 4t2(t2 – 3)(t2 – 2 ) ESSENTIAL QUESTION How can you solve a higher-degree polynomial equation? Factor the polynomial completely and use the zero product property A company’s income is modeled by the function P = 22x2 – 571 x. What is the value of P when x = 200? Lesson 5: Apply the Remainder and Factor Theorem ESSENTIAL QUESTION If you know one zero of a polynomial function, how can you determine another zero? VOCABULARY • Polynomial long division: A method used to divide polynomials similar to the way you divide numbers • Synthetic division: A method used to divide a polynomial by a divisor of the form x - k EXAMPLE 1 Use polynomial long division Divide f (x) = 3x4 – 5x3 + 4x – 6 by x2 – 3x + 5. SOLUTION Write polynomial division in the same format you use when dividing numbers. Include a “0” as the coefficient of x2 in the dividend. At each stage, divide the term with the highest power in what is left of the dividend by the first term of the divisor. This gives the next term of the quotient. EXAMPLE 1 Use polynomial long division 3x2 + 4x – 3 x2 – 3x + 5 )3x4 – 5x3 + 3x4 – 9x3 + quotient 0x2 + 4x – 6 Multiply divisor by 3x4/x2 = 3x2 15x2 4x3 – 15x2 + 4x 4x3 – 12x2 + 20x –3x2 – 16x – 6 –3x2 + 9x – 15 –25x + 9 Subtract. Bring down next term. Multiply divisor by 4x3/x2 = 4x Subtract. Bring down next term. Multiply divisor by – 3x2/x2 = – 3 remainder EXAMPLE 1 Use polynomial long division ANSWER 3x4 – 5x3 + 4x – 6 x2 – 3x + 5 = 3x2 + 4x – 3 + –25x + 9 x2 – 3x + 5 CHECK You can check the result of a division problem by multiplying the quotient by the divisor and adding the remainder. The result should be the dividend. (3x2 + 4x – 3)(x2 – 3x + 5) + (–25x + 9) = 3x2(x2 – 3x + 5) + 4x(x2 – 3x + 5) – 3(x2 – 3x + 5) – 25x + 9 = 3x4 – 9x3 + 15x2 + 4x3 – 12x2 + 20x – 3x2 + 9x – 15 – 25x + 9 = 3x4 – 5x3 + 4x – 6 EXAMPLE 2 Use polynomial long division with a linear divisor Divide f(x) = x3 + 5x2 – 7x + 2 by x – 2. x2 + 7x + x–2 ) x3 + 5x2 – 7x + quotient 7 2 x3 – 2x2 Multiply divisor by x3/x = x2. 7x2 – 7x Subtract. 7x2 – 14x Multiply divisor by 7x2/x = 7x. 7x + 2 Subtract. 7x – 14 Multiply divisor by 7x/x = 7. 16 ANSWER x3 + 5x2 – 7x +2 x–2 remainder = x2 + 7x + 7 + 16 x–2 for Examples 1 and 2 GUIDED PRACTICE Divide using polynomial long division. 1. (2x4 + x3 + x – 1) ANSWER 2. (2x2 – 3x + 8) + (x3 – x2 + 4x – 10) ANSWER (x2 + 2x – 1) –18x + 7 x2 + 2x – 1 (x + 2) (x2 – 3x + 10) + –30 x+2 EXAMPLE 3 Use synthetic division Divide f (x)= 2x3 + x2 – 8x + 5 by x + 3 using synthetic division. SOLUTION –3 2 1 2 ANSWER –8 5 –6 15 –21 –5 7 –16 2x3 + x2 – 8x + 5 x+3 = 2x2 – 5x + 7 – 16 x+3 EXAMPLE 4 Factor a polynomial Factor f (x) = 3x3 – 4x2 – 28x – 16 completely given that x + 2 is a factor. SOLUTION Because x + 2 is a factor of f (x), you know that synthetic division to find the other factors. –2 –4 3 –28 –6 3 –10 –16 20 –8 16 0 f (–2) = 0. Use EXAMPLE 4 Factor a polynomial Use the result to write f (x) as a product of two factors and then factor completely. f (x) = 3x3 – 4x2 – 28x – 16 = (x + 2)(3x2 – 10x – 8) = (x + 2)(3x + 2)(x – 4) Write original polynomial. Write as a product of two factors. Factor trinomial. for Examples 3 and 4 GUIDED PRACTICE Divide using synthetic division. 3. (x3 + 4x2 – x – 1) (x + 3) ANSWER x2 + x – 4 + 11 x+3 4. (4x3 + x2 – 3x + 7) (x – 1) ANSWER 4x2 + 5x + 2 + 9 x–1 for Examples 3 and 4 GUIDED PRACTICE Factor the polynomial completely given that x – 4 is a factor. 5. f (x) = x3 – 6x2 + 5x + 12 ANSWER 6. (x – 4)(x –3)(x + 1) f (x) = x3 – x2 – 22x + 40 ANSWER (x – 4)(x –2)(x +5) ESSENTIAL QUESTION If you know one zero of a polynomial function, how can you determine another zero? Use synthetic division and factor the results to find the other zeros.