(1分之x+1分之y)/(1分之x²-1分之y²)怎么解!速度回答

(1分之x+1分之y)/(1分之x²-1分之y²)怎么解!速度回答
(1分之x+1分之y)/(1分之x²-1分之y²)怎么解!速度回答

(1分之x+1分之y)/(1分之x²-1分之y²)怎么解!速度回答
都写反了,是x分之1,y分之1,……
(1/x+ 1/y)/(1/x²-1/y²)
=[(x+y)/(xy)]/[(y²-x²)/(x²y²)]
=(x+y)x²y²/[xy(y²-x²)]
=(x+y)x²y²/[xy(x+y)(y-x)]
=xy/(y-x)