Question

find the value of of k if x-1=0 is a factor of xcube+2xcube-kx+10

Answer 1

( x -1) is factor of

x³ + 2x³ - kx + 10 = 0

1³ + 2(1)³ - k(1) + 10 = 0

1 + 2 - k + 10 = 0

-k + 13 = 0

-k = -13

k = 13

Answer 2

Answer:

Equation p(x): x³ + 2x³ - kx + 10

Simplified Equation p(x) = 3x³ - kx + 10

Now it is given that (x-1) is a factor of the above equation. Hence if we substitute x = 1, we would get the answer as 0.

Substituting x = 1, we get:

⇒ 3(1)³ - k(1) + 10 = 0

⇒ 3 - k + 10 = 0

⇒ 13 - k = 0

⇒ k = 13

Hence the value of k is 13 if (x-1) is a factor of the given equation.