几道分式的的化简题①9a²-12ab+4b²/4b²-9a²②y-x四次方y/x²y-2xy+y③(1-x)³/(x-1)四次方

问题描述:

几道分式的的化简题
①9a²-12ab+4b²/4b²-9a²
②y-x四次方y/x²y-2xy+y
③(1-x)³/(x-1)四次方

(3a-2b)平方/(2b+3a)(2b-3a)=-(3a-2b)/2b+3a)
y(1-x四次方)/y(x-1)平方=(1-x)平方=1-2x+x平方
(1-x)分之1