傲赴阿尔卑
幼苗
共回答了14个问题采纳率：78.6% 举报
∵1/(x-7)+1/(x-8)=-1/(x-10)-1/(x-11)
∴1/(x-7)+1/(x-8)+1/(x-10)+1/(x-11)=0
∴（x-7+x-8+x-10+x-11）/(x-7)(x-8)(x-10)(x-11)=0
∵分母不为0
∴(x-7)(x-8)(x-10)(x-11)不=0
∵ （x-7+x-8+x-10+x-11）/(x-7)(x-8)(x-10)(x-11)=0
∴x-7+x-8+x-10+x-11=0
∴4x-36=0
∴x=9
1年前
6
