数学问题(10)

我认为你的式子是
[7/(x^2+x)]+[3/(x^2-x)]=6/(x^2-1)
[7/x(x+1)]+[3/x(x-1)]=6/[(x+1)(x-1)]
两边同时乘以x(x+1)(x-1)，则
7(x-1)+3(x+1)=6x
7x-7+3x+3=6x
x=1

7/(x^2+x)+3/(x^2-x)=6/(x^2-1)
方程两边同时乘以x(x+1)(x-1)
7(x-1)+3(x+1)=6x
x=1
经检验，x=1是原方程的解