Find the value of k if y – 1 is a factor of y3 + 4y2 + ky – 6
-
A.
-6 -
B.
-4 -
C.
O -
D.
1
Correct Answer: Option D
Explanation
if y – 1 is a factor of y3 + 4y2 + ky – 6, then
f(1) = (1)3 + 4(1)2 + k(1) – 6 = 0 (factor theorem)
1 + 4 + k – 6 = 0
5 – 6 + k = 0
-1 + k = 0
k = 1
There is an explanation video available below.