化简求值:(x^2-y^2)/x乘以2x/(x^2-2xy+y^2),其中x=2,y=1
问题描述:
化简求值:(x^2-y^2)/x乘以2x/(x^2-2xy+y^2),其中x=2,y=1
答
=(x+y)(x-y)/x×2x/(x-y)²
=(x+y)×2/(x-y)
=2(x+y)/(x-y)
=6