化简求值1.x^2+2xy+y^2/x^2-y^2除以x^2+xy/xy-y^2X=1Y=-2011
问题描述:
化简求值
1.
x^2+2xy+y^2/x^2-y^2除以x^2+xy/xy-y^2
X=1
Y=-2011
答
认真听课
答
x^2+2xy+y^2/x^2-y^2除以x^2+xy/xy-y^2
=(x+y)²/(x+y)(x-y) ÷x(x+y)/y(x-y)
=(x+y)/(x-y) × y(x-y)/x(x+y)
=y/x
再将X=1
Y=-2011代入
原式=y/x
=﹣2011