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5.4 Dividing Polynomials

Long division of one polynomial by another and the faster synthetic division by a linear factor, reading off the quotient and remainder each time.

Algebra and Trigonometry 2e, 5.4 Dividing Polynomials

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38 exercises

5.4 Exercise 13

Divide 16 x 3 −12 x 2 +20x−3 16 x^{3} - 12 x^{2} + 20 x - 3 by 4x+5. 4 x + 5.

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5.4 Exercise 17

Use synthetic division to divide 3 x 4 +18 x 3 −3x+40 3 x^{4} + 18 x^{3} - 3 x + 40 by x+7. x + 7.

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5.4 Exercise 19

The area of a rectangle is given by 3 x 3 +14 x 2 −23x+6. 3 x^{3} + 14 x^{2} - 23 x + 6. The width of the rectangle is given by x+6. x + 6. Find an expression for the length of the rectangle.

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5.4 Exercise 20

If division of a polynomial by a binomial results in a remainder of zero, what can be conclude?

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5.4 Exercise 22

Use long division to divide. Specify the quotient and the remainder.

( x 2 +5x−1 )÷( x−1 ) \left(x^{2} + 5 x - 1\right) \div \left(x - 1\right)

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5.4 Exercise 24

Use long division to divide. Specify the quotient and the remainder.

( 3 x 2 +23x+14 )÷( x+7 ) \left(3 x^{2} + 23 x + 14\right) \div \left(x + 7\right)

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5.4 Exercise 26

Use long division to divide. Specify the quotient and the remainder.

( 6 x 2 −25x−25 )÷( 6x+5 ) \left(6 x^{2} - 25 x - 25\right) \div \left(6 x + 5\right)

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5.4 Exercise 28

Use long division to divide. Specify the quotient and the remainder.

( 2 x 2 −3x+2 )÷( x+2 ) \left(2 x^{2} - 3 x + 2\right) \div \left(x + 2\right)

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5.4 Exercise 30

Use long division to divide. Specify the quotient and the remainder.

( 3 x 2 −5x+4 )÷( 3x+1 ) \left(3 x^{2} - 5 x + 4\right) \div \left(3 x + 1\right)

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5.4 Exercise 32

Use long division to divide. Specify the quotient and the remainder.

( 2 x 3 +3 x 2 −4x+15 )÷( x+3 ) \left(2 x^{3} + 3 x^{2} - 4 x + 15\right) \div \left(x + 3\right)

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5.4 Exercise 34

Use synthetic division to find the quotient. Ensure the equation is in the form required by synthetic division. (Hint: divide the dividend and divisor by the coefficient of the linear term in the divisor.)

( 2 x 3 −6 x 2 −7x+6 )÷(x−4) \left(2 x^{3} - 6 x^{2} - 7 x + 6\right) \div \left(x - 4\right)

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5.4 Exercise 36

Use synthetic division to find the quotient. Ensure the equation is in the form required by synthetic division. (Hint: divide the dividend and divisor by the coefficient of the linear term in the divisor.)

( 4 x 3 −12 x 2 −5x−1 )÷(2x+1) \left(4 x^{3} - 12 x^{2} - 5 x - 1\right) \div \left(2 x + 1\right)

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5.4 Exercise 38

Use synthetic division to find the quotient. Ensure the equation is in the form required by synthetic division. (Hint: divide the dividend and divisor by the coefficient of the linear term in the divisor.)

( 3 x 3 −2 x 2 +x−4 )÷( x+3 ) \left(3 x^{3} - 2 x^{2} + x - 4\right) \div \left(x + 3\right)

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5.4 Exercise 40

Use synthetic division to find the quotient. Ensure the equation is in the form required by synthetic division. (Hint: divide the dividend and divisor by the coefficient of the linear term in the divisor.)

( 2 x 3 +7 x 2 −13x−3 )÷( 2x−3 ) \left(2 x^{3} + 7 x^{2} - 13 x - 3\right) \div \left(2 x - 3\right)

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5.4 Exercise 42

Use synthetic division to find the quotient. Ensure the equation is in the form required by synthetic division. (Hint: divide the dividend and divisor by the coefficient of the linear term in the divisor.)

( 4 x 3 −5 x 2 +13 )÷(x+4) \left(4 x^{3} - 5 x^{2} + 13\right) \div \left(x + 4\right)

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5.4 Exercise 44

Use synthetic division to find the quotient. Ensure the equation is in the form required by synthetic division. (Hint: divide the dividend and divisor by the coefficient of the linear term in the divisor.)

( x 3 −21 x 2 +147x−343 )÷( x−7 ) \left(x^{3} - 21 x^{2} + 147 x - 343\right) \div \left(x - 7\right)

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5.4 Exercise 46

Use synthetic division to find the quotient. Ensure the equation is in the form required by synthetic division. (Hint: divide the dividend and divisor by the coefficient of the linear term in the divisor.)

( 9 x 3 −x+2 )÷( 3x−1 ) \left(9 x^{3} - x + 2\right) \div \left(3 x - 1\right)

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5.4 Exercise 48

Use synthetic division to find the quotient. Ensure the equation is in the form required by synthetic division. (Hint: divide the dividend and divisor by the coefficient of the linear term in the divisor.)

( x 4 + x 3 −3 x 2 −2x+1 )÷( x+1 ) \left(x^{4} + x^{3} - 3 x^{2} - 2 x + 1\right) \div \left(x + 1\right)

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5.4 Exercise 50

Use synthetic division to find the quotient. Ensure the equation is in the form required by synthetic division. (Hint: divide the dividend and divisor by the coefficient of the linear term in the divisor.)

( x 4 +2 x 3 −3 x 2 +2x+6 )÷( x+3 ) \left(x^{4} + 2 x^{3} - 3 x^{2} + 2 x + 6\right) \div \left(x + 3\right)

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5.4 Exercise 52

Use synthetic division to find the quotient. Ensure the equation is in the form required by synthetic division. (Hint: divide the dividend and divisor by the coefficient of the linear term in the divisor.)

( x 4 −8 x 3 +24 x 2 −32x+16 )÷( x−2 ) \left(x^{4} - 8 x^{3} + 24 x^{2} - 32 x + 16\right) \div \left(x - 2\right)

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5.4 Exercise 54

Use synthetic division to find the quotient. Ensure the equation is in the form required by synthetic division. (Hint: divide the dividend and divisor by the coefficient of the linear term in the divisor.)

( x 4 −12 x 3 +54 x 2 −108x+81 )÷( x−3 ) \left(x^{4} - 12 x^{3} + 54 x^{2} - 108 x + 81\right) \div \left(x - 3\right)

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5.4 Exercise 56

Use synthetic division to find the quotient. Ensure the equation is in the form required by synthetic division. (Hint: divide the dividend and divisor by the coefficient of the linear term in the divisor.)

( 4 x 4 +2 x 3 −4 x 2 +2x+2 )÷( 2x+1 ) \left(4 x^{4} + 2 x^{3} - 4 x^{2} + 2 x + 2\right) \div \left(2 x + 1\right)

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5.4 Exercise 58

Use synthetic division to determine whether the first expression is a factor of the second. If it is, indicate the factorization.

x−2,3 x 4 −6 x 3 −5x+10 x - 2 , 3 x^{4} - 6 x^{3} - 5 x + 10

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5.4 Exercise 60

Use synthetic division to determine whether the first expression is a factor of the second. If it is, indicate the factorization.

x−2,4 x 4 −15 x 2 −4 x - 2 , 4 x^{4} - 15 x^{2} - 4

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5.4 Exercise 62

Use synthetic division to determine whether the first expression is a factor of the second. If it is, indicate the factorization.

x+ 1 3 ,3 x 4 + x 3 −3x+1 x + \frac{1}{3} , 3 x^{4} + x^{3} - 3 x + 1

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5.4 Exercise 68

Use synthetic division to find the quotient and remainder.

4 x 3 −33 x−2 \frac{4 x^{3} - 33}{x - 2}

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5.4 Exercise 70

Use synthetic division to find the quotient and remainder.

3 x 3 +2x−5 x−1 \frac{3 x^{3} + 2 x - 5}{x - 1}

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5.4 Exercise 72

Use synthetic division to find the quotient and remainder.

x 4 −22 x+2 \frac{x^{4} - 22}{x + 2}

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5.4 Exercise 74

Use a calculator with CAS to answer the questions.

Consider x k +1 x+1 \frac{x^{k} + 1}{x + 1} for k=1, 3, 5. k = 1 , 3 , 5. What do you expect the result to be if k=7? k = 7 ?

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5.4 Exercise 76

Use a calculator with CAS to answer the questions.

Consider x k x+1 \frac{x^{k}}{x + 1} with k=1, 2, 3. k = 1 , 2 , 3. What do you expect the result to be if k=4? k = 4 ?

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5.4 Exercise 78

Use synthetic division to determine the quotient involving a complex number.

x+1 x−i \frac{x + 1}{x - i}

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5.4 Exercise 80

Use synthetic division to determine the quotient involving a complex number.

x+1 x+i \frac{x + 1}{x + i}

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5.4 Exercise 82

Use synthetic division to determine the quotient involving a complex number.

x 3 +1 x−i \frac{x^{3} + 1}{x - i}

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5.4 Exercise 84

Use the given length and area of a rectangle to express the width algebraically.

Length is 2x+5, 2 x + 5 , area is 4 x 3 +10 x 2 +6x+15 4 x^{3} + 10 x^{2} + 6 x + 15

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5.4 Exercise 86

Use the given volume of a box and its length and width to express the height of the box algebraically.

Volume is 12 x 3 +20 x 2 −21x−36, 12 x^{3} + 20 x^{2} - 21 x - 36 , length is 2x+3, 2 x + 3 , width is 3x−4. 3 x - 4.

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5.4 Exercise 88

Use the given volume of a box and its length and width to express the height of the box algebraically.

Volume is 10 x 3 +27 x 2 +2x−24, 10 x^{3} + 27 x^{2} + 2 x - 24 , length is 5x–4, 5 x – 4 , width is 2x+3. 2 x + 3.

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5.4 Exercise 90

Use the given volume and radius of a cylinder to express the height of the cylinder algebraically.

Volume is π(25 x 3 −65 x 2 −29x−3), \pi \left(25 x^{3} - 65 x^{2} - 29 x - 3\right) , radius is 5x+1. 5 x + 1.

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5.4 Exercise 92

Use the given volume and radius of a cylinder to express the height of the cylinder algebraically.

Volume is π(3 x 4 +24 x 3 +46 x 2 −16x−32), \pi \left(3 x^{4} + 24 x^{3} + 46 x^{2} - 16 x - 32\right) , radius is x+4. x + 4.

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Adapted from College Algebra © 2021 Rice University. Licensed under CC BY 4.0. Sources: College Algebra 2e, Algebra and Trigonometry 2e, Precalculus 2e, College Algebra with Corequisite Support 2e. Imported at revision 4922e46.