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43 votes
Type the correct answer in the box. Use numerals Instead of words. If necessary, use the fraction bar.

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User Gas
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1 Answer

24 votes
24 votes

We must find the value k such that Q(x) = (x+2) is a factor of the cubic polynomial:


P(x)=x^3-6x^2-11x+k

Now, if (x+2) is a factor of the polynomial P(x), then the rest R of the following division must be zero,


(P(x))/(Q(x))

So we must compute the division between the polynomials and check the condition to have R = 0. We compute the quotient by applying the method of synthetic division. Doing that we have:

From the division we see that the rest is:


R=k-10

The condition is that the rest R must be equal to zero, so:


R=k-10=0\Rightarrow k=10

Answer: k = 10

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User Douglas Correa
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