x/y+y/x=-1 

Then  find the value of x³-y³

Asked by samarthnagpal254 | 25th Aug, 2019, 07:19: PM

Expert Answer:

We know that,x3 - y3 = (x - y)(x² + xy + y²) ....(i)
Given that, x/y + y/x = -1
(x² + y²)/xy = -1
x² + y² = -xy
x² + y² + xy = 0
(x² + xy + y²) = 0
Multyplying by (x - y) on both sides we get,(x - y)(x² + xy + y²) = (x - y) × 0
x3 - y3 = 0    using (i)

Answered by Sneha shidid | 26th Aug, 2019, 09:21: AM