Question

Simplify (x + y)3

- (x - y)3

- 6y(x + y) (x - y).​

Answer 1

Answer:

(x+y)^3-(x-y)^3-6y(x+y)(x-y)

=(x+y)^3-(x-y)^3-3(x+y)(x-y){(x+y)-(x-y)

={(x+y)-(x-y)}^3

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

=(2y)^3

=8y^3