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(r^3+2r^2-7r-12) / (r+3) polynomial division

User Acmerfight
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Final answer:

To divide the polynomial r^3+2r^2-7r-12 by r+3, we use polynomial long division. The quotient is r^2 - r - 4 and the remainder is 0.

Step-by-step explanation:

To divide the polynomial r^3+2r^2-7r-12 by r+3, we can use polynomial long division. Here are the steps:

  1. Write the polynomial in descending order of powers of r: r^3+2r^2-7r-12
  2. Divide the first term of the dividend by the first term of the divisor: r^3 / (r+3) = r^2
  3. Multiply the divisor by the result of the previous step: (r+3) * r^2 = r^3 + 3r^2
  4. Subtract the product from the dividend: (r^3+2r^2-7r-12) - (r^3 + 3r^2) = -r^2-7r-12
  5. Repeat the process with the remainder: -r^2-7r-12 / (r+3)
  6. Divide the first term of the new dividend by the first term of the divisor: -r^2 / (r+3) = -r
  7. Multiply the divisor by the result of the previous step: (r+3) * -r = -r^2 - 3r
  8. Subtract the product from the new dividend: (-r^2-7r-12) - (-r^2 - 3r) = -4r-12
  9. The new dividend is -4r-12, which is a linear polynomial. Divide it by the divisor: -4r / (r+3) = -4
  10. Multiply the divisor by the result of the previous step: (r+3) * -4 = -4r -12
  11. Subtract the product from the new dividend: (-4r-12) - (-4r - 12) = 0

The quotient is r^2 - r - 4 and the remainder is 0. Therefore, the division is exact and the answer is the quotient: r^2 - r - 4.

User Zagoa
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