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What is the remainder of f(x)=x^3+x^2-9x+23 When divided by binomial X +4

User Scott Cranfill
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1 Answer

14 votes
14 votes

Answer:

The remainder is 11.

Explanation:

We are given the polynomial:


f(x) = x^3 + x^2 - 9x + 23

And we want to find its remainder when the polynomial is divided by:


x + 4

We can use the Polynomial Remainder Theorem. According to the PRT, if we divide a polynomial P(x) by a binomial in the form (x - a), the remainder will be given by P(a).

In this case, our binomial is (x + 4) or (x - (-4)). Hence, a = -4.

Then the remainder will be f(-4):


\displaystyle \begin{aligned}f(-4) &= (-4)^3 + (-4)^2 - 9(-4) + 23 \\ &= 11 \end{aligned}

In conclusion, the remainder of the operation is 11.

User Gandalf The White
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