Question

If x = 1 is a zero of the polynomial f(x) = x³ − 2x² + 4x + k, write the value of k.

Answer 1

We have to find the value of K if  x = 1 is a zero of the polynomial f(x) = x³ − 2x² + 4x + k.

`f (x)= x^3 - 2x^2 + 4x + k`

`f(1)= 1^3 -2 (1)^2+ 4 xx1 + k`

`0 = 1 - 2 + 4 + k`

`0 = 5 - 2 + k `

`0 = 3 + k`

` - 3 = k `

Hence, the value of k is k = - 3