1/(x-6)+1/(x-12)=1/(x-7)+1/(x-11)

问题描述:

1/(x-6)+1/(x-12)=1/(x-7)+1/(x-11)

1/(x-12)-1/(x-11)=1/(x-7)-1/(x-6)[(x-11)-(x-12)]/(x-12)(x-11)=[(x-6)-(x-7)]/(x-6)(x-7)1/(x-12)(x-11)=1/(x-6)(x-7)(x-6)(x-7)=(x-12)(x-11)x²-13x+42=x²-23x+13210x=90∴x=9检验:x=9是方程的解...如果直接通分,为什么会无解有解的,关键看分子不可将两边的(2x-18)约去 请采纳