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Lorie is using long division to find the quotient of x^3 + 6x^2 + 5 and x^2 + x -1, as shown at the bottom of this question.

What mistake did Lorie make?

A. She added an extra term to the dividend.

B. She combined the constants incorrectly in the last step.

C. The second term in the quotient should be 7.

D. The last term in the quotient has an incorrect denominator.

Lorie is using long division to find the quotient of x^3 + 6x^2 + 5 and x^2 + x -1, as-example-1

2 Answers

2 votes

Lorie made a mistake in the subtraction and combination of constants during polynomial long division, which is a critical step in the overall division process.

  • In reviewing the division of polynomials provided by Lorie, the mistake that was made appears to be related to the incorrect subtraction and combination of constants in the last step.
  • When performing polynomial long division, it's important to correctly subtract polynomial expressions and combine like terms.
  • Lorie should have subtracted the entire polynomial expression after multiplying by the term found in the quotient.
  • This process is akin to dividing exponentials, where the division of terms is performed by subtracting the exponents of exponential terms.
  • To ensure the correct result, every step of the polynomial long division must be done with meticulous care to avoid mistakes in subtraction or overlooking terms that should be combined.

Question:

Lorie is using long division to find the quotient of x^3+6x^2+5 and x^2+x-1 , as shown. x+5- 4x/x^2+x-1 x^2+x-1overline )x^3+6x^2+0x+5 - ((x^3+x^2-x))/5x^2+x +5 - ((5x^2+5x-5))/-4x+0 What mistake did Lorie make?

A. The second term in the quotient should be 7

B. She combined the constants incorrectly in the last step..

C. She added an extra term to the dividend.

D. The last term in the quotient has an incorrect denominator.

User Jcwenger
by
5.6k points
0 votes

Answer:

Option (B)

Explanation:

x² + x - 1) x³ + 6x² + 0x + 5 ( x + 5

- (x³ + x² - x)

5x² + x + 5

-(5x² + 5x - 5)

-4x + 10

Result :
x+5+(-4x+10)/((x^(2)+x-1))

By the comparing the result with the Lorie's solution,

She made a mistake in the last step in which she combined the constant incorrectly.

Therefore, Option (B) will be the answer.

User Tejus Prasad
by
5.9k points