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幼苗
共回答了30个问题采纳率:96.7% 举报
(X-1)[1-(X+1)/(X-1/X)]
= (X-1)[ 1- (X+1) (X/(X²-1)]
= (X-1)[1-(X²+X)/(X²-1)]
= (X-1){(X²-1-X²-X)/(X²-1)
= (X-1){(-X-1)/[(X+1)(X-1)]}
= (-(X+1) {(X-1))/[(X+1)(X-1)]}
= -1
如果写在作业本或者试卷上,就不用写大括号的了;我是因为这里写分数线写不了,才加了个大括号上去,方便看
1年前
10