Question

Find the value of k if (x-3) is a factor of P(x)=2x3-5x2+3x+k

Answer 1

k = -18

Explanation:

If x-3 is a factor, what this means is that if we substitute;

x = 3 into the equation, we should get 0

This is from the factor theorem

Thus ;

P(3) = 0 = 2(3)^3 -5(3)^2 + 3(3) + k

0 = 54 - 45 + 9 + k

k + 18 = 0

k = -18