Question

Find the value of k if:
(x+3)is a factor of 3x^3 + Kx +6.
please help me to calculate this I know only the answer that is = -25 but I don't know how to calculate please help​

Answer 1

Step-by-step explanation:

Here x+3 is a factor of 3x³+Kx+6

x=-3

f(-3)=0 because it is a factor

f(-3)=3x³+Kx+6

3(-3³)+k(-3)+6=0

-81-3k+6=0

-75-3k=0

-3k=75

k=75/-3k=-25