Question

if alpha and beta are two zeros of the quadratic polynomial x square minus x minus 4 then find the values of 1 by alpha plus 1 by beta minus alpha beta

Answer 1

x^2-x-4
alpha +beta=-b/a
=1

alpha*beta=c/a=-4

1/alpha+1/beta

take lcm


(alpha+beta)/(alpha*beta)
1/-4
-1/4 is the answer

Answer 2

x²-x-4
a=1 , b=-1, c=-4
 now after putting relations you will find values of alpha plus beta and alpha beta
now after simplifying the equation 1 by alpha .. you will just need to put the values you got after puttuing relations(alph=beta=-b/a, alpha beta=c/a)
then just solve itand you will get -17/4