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Question

(x-y)^-2/(x^-2-y^-2)

 

Answer 1

The expression is (x-y)^-2/(x^-2-y^-2).

= [1/(x - y)²] / (1/x² - 1/y²)

= [1/(x - y)²] / [(y² - x²)/x²y²]

= [1/(x - y)²] * [x²y²/(y² - x²)]

= x²y²/(x - y)²(y² - x²)

= x²y²/[(x - y)²(y - x)(y + x)]

= - x²y²/[(x - y)²(x - y)(x + y)]

= - x²y²/[(x - y)³(x + y)]