Y的平方+2Y+1分之xy+x
问题描述：
Y的平方+2Y+1分之xy+x
答
=x(y+1)/(y+1)²
=x/(y+1)
答
解
(xy+x)/(y²+2y+1)
=x(y+1)/(y+1)²
=x/(y+1)