How do you determine the value of k if the remainder is 3 given (x^3+x^2+kx-15) div(x-2)(x3+x2+kx15)÷(x2)?

1 Answer
Dec 24, 2016

Use the remainder theorem to find k = 3k=3

Explanation:

Let f(x) = x^3+x^2+kx-15f(x)=x3+x2+kx15

By the remainder theorem, the remainder when f(x)f(x) is divided by (x-2)(x2) will be f(2)f(2)

So we have:

3 = f(2) = 8+4+2k-15 = 2k-33=f(2)=8+4+2k15=2k3

Add 33 to both ends to get:

6 = 2k6=2k

Divide both sides by 22 and transpose to get:

k = 3k=3