Question

expand (x-y-3)2 using formula​

Answer 1

Answer:

The expression (x-y)3 can be written as, (x-y)(x-y)(x-y)

First simplify (x-y)(x-y) by binomial multiplication.

(x-y)(x-y) = x2 - 2xy + y2

Now multiply (x-y) with x2 - 2xy + y2

(x-y)(x-y)(x-y) = (x-y)(x2 - 2xy + y2)

= x3 - 2x2y + xy2 - yx2 + 2xy2 - y3

= x3 - 3x2y + 3xy2 - y3

Thus, the expansion of (x-y)3 is x3 - y3 - 3x2y + 3xy2