x+1/x+2 + x+6/x+7 =x+2/x+3 + x+5/x+6 多少了!

x+1/x+2 + x+6/x+7 =x+2/x+3 + x+5/x+6 多少了!
x+1/x+2 + x+6/x+7 =x+2/x+3 + x+5/x+6 多少了!

x+1/x+2 + x+6/x+7 =x+2/x+3 + x+5/x+6 多少了!
x+1/x+2 + x+6/x+7 =x+2/x+3 + x+5/x+6
1-1/(x+2)+1-1/(x+7)=1-1/(x+3)+1-1/(x+6)
1/(x+6)-1/(x+7)=1/(x+2)-1/(x+3)
1/(x+6)(x+7)=1/(x+2)(x+3)
(x+6)(x+7)=(x+2)(x+3)
13x+42=5x+6
8x=-36
x=-4.5
经检验x=-4.5是方程的根.

两边同时乘以(x+2)(x+7)(x+3)(x+6)
变为 (x+1)(x+3)(x+7)(x+6)+(x+2)(x+3)(x+6)(x+6)=(x+2)(x+2)(x+7)(x+6)+(x+2)(x+3)(x+5)(x+7)