Login

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

We have,px = kx2 - 4x + k, as the given polynomialSince,  -1 is a zero of px, then,p-1 = 0⇒ k -12 -4 -1 + k = 0⇒ k + 4 + k = 0⇒2k = -4⇒ k = -2

  • 0
View Full Answer

put value of x

k(-1*-1)-4*-1+k =0

1k+4+k = 0

2k=-4

k=-4/2

k=-2

  • -1

p(x) = kx2 - 4x + k

Since -1 is a zero of p(x)

p(-1) = 0

k(-1)2 - 4(-1) + k = 0

k + 4 + k = 0

2k = -4

k = -2

So, value of k = -2

  • 2
What are you looking for?