来源:学生作业帮 编辑:搜狗做题网作业帮 分类:数学作业 时间:2024/07/07 04:38:10
有点急
![](http://img.wesiedu.com/upload/2/14/2143edfe31ad7dd08fdea4456bb7e482.jpg)
∵abc=1
∴ab+a+1=ab+a+abc=a(b+bc+1)
ca+c+1=ca+c+abc=c(a+ab+1)
∴原式
=(b+1)/(b+bc+1)+1/(a+ab+1)
=a(b+1)/a(b+bc+1)+1/(a+ab+1)
=a(b+1)/(ab+abc+a)+1/(a+ab+1)
=a(b+1)/(ab+a+1)+1/(a+ab+1)
=(ab+a+1)/(a+ab+1)
=1