Question

find the value of k if -1 is zero of the polynomial p(x)= kx² - 4 x + k​

Answer 1

p(x) = kx^2 - 4x + k
p(-1) = -1x^2 - 4x + (-1)
p(-1) = -x^2 - 4x - 1
p(-1) = (-x)(-x) - 4x - 1
p(-1) = x - 4x - 1
- 1 = -3x
1/3 = x

Therefore, the value of k is 1/3

Answer 2

Step-by-step explanation:

Put value of x =-1

P(-1) = k×[-1] - 4×[-1] ± k =0

k+4+k =0

2k+4=0

2k= -4

K=-4/2

k= -2