“除以”后边有括号吗?如果有的话：
(x减y分之1+x+y分之1)除以x的平方减2xy+y的平方分之2x
=(x-1/y+x+1/y)÷(x²-2xy+2x/y²)
=2x÷(x²-2xy+2x/y²)
=2x÷[(x²y²-2xy³+2x)/y²]
=2x[y²/(x²y²-2xy³+2x)]
=2xy²/(x²y²-2xy³+2x)
=2y²/(xy²-2y³+2)
如果没有的话：
=(x-1/y+x+1/y)÷x²-2xy+2x/y²
=2x÷x²-2xy+2x/y²
=2/x-2xy+2x/y²
=2(1/x-xy+1/y²)
=2(y²-x²y³+x)/xy²