初二数学分式化简已知x-3y=0(xy不等于0),求【(2x+y)/(x²-2xy+y²)】*(x-y)的值先化简,在带入

问题描述:

初二数学分式化简
已知x-3y=0(xy不等于0),求【(2x+y)/(x²-2xy+y²)】*(x-y)的值
先化简,在带入

x-3y=0
所以x=3y
代入
原式=[(2x+y)/(x-y)²](x-y)
=(2x+y)/(x-y)
=(6y+y)/(3y-y)
=7y/2y
=7/2

原式=(2x+y)/(x-y)
x-3y=0 所以x=3y
代入得
原式=(6y+y)/(3y-y)
=7y/2y
=7/2