计算：(1) x+2y+(4y^2/x-2y) (2) (x/x^2-1)除以(x^2+4x+3)/(x^2+2x+1) (3) 12/(m^2-9)加上2/(3-m)
问题描述：
计算：(1) x+2y+(4y^2/x-2y) (2) (x/x^2-1)除以(x^2+4x+3)/(x^2+2x+1) (3) 12/(m^2-9)加上2/(3-m)
x+2y+4y^2/(x-2y) 第一小题
答
（1）：(x+2y)+4y²/(x-2y)=[(x+2y)(x-2y)+4y²]/(x-2y)=x²/(x-2y)（2）：(x²+4x+3)/(x²+2x+1)=[(x+1)(x+3)]/(x+1)²=(x+3)/(x+1),所以原式=x/(x²-1)/[(x+3)/(x+1)]（我想你应该是...