Question

if alfa and beta are the zeroes of the quadratic polynomial p(x) = x2+kx+45 such that (alfa-beta)2= 144, find the value of k

Answer 1

(alpha-beta)^2 = alpha2 + beta2 -2alpha beta

= (alpha+beta) ^2 -4 alpha beta

= k^2 - 180 = 144
k = 18

Answer 2

hope this will help uu... :-)