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"

A student used synthetic division to divide x^3-x^2-2x by x+1.
A. identify and describe the errors in the student's setup for the synthetic division.
B. Show the correct setup with calculations.
C. using the Remainder Theorem and the Factor theorem (p.2x+1) is a factor of the polynomial? If it is a factor, who the fully factored form of the polynomial."

User Fydelio
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Final answer:

The errors in the student's setup for synthetic division are misplacing the sign of the constant term and not including the coefficient of the x term. The correct setup for synthetic division is provided along with the steps. The Remainder Theorem and the Factor theorem are explained to determine if x+1 is a factor of the polynomial and the fully factored form of the polynomial is explained if it is a factor.

Step-by-step explanation:

The errors in the student's setup for synthetic division are:

  1. Misplacing the sign of the constant term.
  2. Not including the coefficient of the x term.

The correct setup for synthetic division is as follows:

x^3-x^2-2x / (x+1)

  1. Arrange the terms in descending order of degree.
  2. Write down the coefficients of each term, including the missing coefficients. In this case, the coefficient of x is 0.
  3. Reverse the sign of the constant term.
  4. Bring down the leading coefficient.
  5. Multiply the divisor by the first term.
  6. Subtract the result from the second term.
  7. Multiply the divisor by the new result.
  8. Repeat steps 6 and 7 until all terms have been divided.
  9. The resulting coefficients are the coefficients of the quotient polynomial.

Using the Remainder Theorem and the Factor theorem, we can determine if x+1 is a factor of the polynomial:

Remainder Theorem: If x+1 is a factor of the polynomial, the remainder when dividing the polynomial by x+1 will be 0.

Factor Theorem: If x+1 is a factor of the polynomial, then x = -1 is a solution to the polynomial equation.

To check if x+1 is a factor, we substitute x = -1 into the polynomial and see if it equals 0. If it does, then x+1 is a factor of the polynomial.

If x+1 is a factor, then the fully factored form of the polynomial can be found by dividing the original polynomial by x+1.

User RiverHeart
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