Question

If a =1 -root3 then find the value of (a-1/a)^3

Answer 1

Answer:

Given a+1/a=1

multiply with a^2 both sides

a^3+a=a^2_______(1)

=>a(a^2+1)=a^2

=>a^2=a-1;

now from 1, a^3=a^2-1=>a^3+a=a-1=>a^3=-1