Question

if x/y+y/x=-1 (x,yis not =0) find value of x^3-y^3
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Answer 1

x/y + y/x = -1

(x^2 + y^2)/xy = -1

x^2 + y^2 = -xy

x^2 + xy + y^2 = 0……….(i)

(x^3 - y^3) = (x-y)(x^2 + xy + y^2)

Substituting (i),we get :

(x^3 - y^3) = (x-y)(0)

x^3 - y^3 = 0