Question

Find the value of ‘k’ if x -1 is a factor of P(x) = 4$x^3$ + $x^2$ – 3x + k.

• A. -1
• B. -2
• C. -3
• D. -4

Answer 1

The correct option is B

-2

Since x-1 is the factor of 4$x^3$ + $x^2$ – 3x + k, therefore at x = 1,

P(x) = 0

So, 4${\left(1\right)}^3$ + ${\left(1\right)}^2$ – 3(1) + k = 0

i.e, 2 + k = 0

k = -2