Question

Find the value of k so that polynomials x cube + 3 x square - kx - 3 has one factor as x + 3

Answer 1

Hey

Here is your answer,

X+3 = 0 ( it is a factor )
X = -3

Substitute the value of x in equation,

X^3 + 3x^2 - kx - 3 = 0
(-3)^3 + 3(-3)^2 - k(-3) - 3 = 0
-27 - 27 + 3k - 3 = 0
-57 + 3k = 0
3k = 57
k = 57/3
k = 19

Hope it helps you!