问题描述： （2X-3Y)（3X-4Y）=0求(X平方-2XY)/(X+Y)(X-2Y) 1个回答 分类：数学 2014-11-30 问题解答： 我来补答 （2X-3Y)（3X-4Y）=0若2X-3Y=0 则X=3Y/2 代入得[(3Y/2)^2-2*(3Y/2)*Y]/(3Y/2+Y)(3Y/2-2Y)=(9Y^2/4-3Y^2)/(5Y/2)(-Y/2)=(-3Y^2/4)/(-5Y^2/4)=3/5若3X-4Y=0 则X=4Y/3 代入得[(4Y/3)^2-2*(4Y/3)*Y]/(4Y/3+Y)(4Y/3-2Y)=(16Y^2/9-8Y^2/3)/(7Y/3)(-2Y/3)=(-8Y^2/9)/(-14Y^2/9)=4/7 展开全文阅读
