Question

Given f(x) = 3x^3 + kx – 5, and x – 1 is a factor of f(x), then what is the value of k?

Answer 1

Answer:

$\large \color{lime}{ \boxed{ \boxed{ \sf{ \: k = -4}}}}$

The value of k is -4.

Given that,

• The equation is f(x) = 3x^3 + kx + 1f(x)=3x3+kx+1 .And, x - 1 is the factor of f(x).
• Based on the above information, the calculation is as follows:

f (x) = 3x³ + kx + 1

= 3 (1)³ + k (1) + 1

= 3 + k + 1

K= -4

Therefore, we can conclude that the value of k is -4.

Learn more: brainly.com/question/16115373

Answer 2

Step-by-step explanation:

$f(x) = {3x}^{3} + kx - 5 \\ \\ x - 1 \: is \: \: a \: factor \: of \: f(x) \\ f(1) = 0 .........(1) \\ f(1) = 3 \times {1}^{3} + k \times 1 - 5 \\ = 3 + k - 5..........(2) \\ \\ (1) = (2) \\ 3 + k - 5 = 0 \\ k = 2$