初中一道数学问题

来源：百度知道编辑：UC知道时间：2024/05/18 01:35:17

6/＜(x+1)(x-1)＞该怎么变成3/(x-1)-3/(x+1)

6/[(x+1)(x-1)]
=[3(x+1)-3(x-1)]/[(x+1)(x-1)]
=3(x+1)/[(x+1)(x-1)]-3(x-1)/[(x+1)(x-1)]
=3/(x-1)-3/(x+1)
多多练练一眼就能看出来了啦

就是直接把分母拆开就可以得到了！！！

这个没什么技巧的！！

6/(X+1)(X-1)=3*2/(X+1)(X-1)=3[1/(X-1)-1/(X+1)]=3/(X-1)-3/(X+1)

6/[(x+1)(x-1)]
=[3(x+1)-3(x-1)]/[(x+1)(x-1)]
=3(x+1)/[(x+1)(x-1)]-3(x-1)/[(x+1)(x-1)]
=3/(x-1)-3/(x+1)

原式=<3(x+1)-3(x-1)>/(x+1)(x-1)
=3(x+1)/(x+1)(x-1)-3(x-1)/(x+1)(x-1)
=3/(x-1)-3/(x+1)

6*0.5[(x+1)-(x-1)]/[(x+1)(x-1)]
=3[(x+1)-(x-1)]/[(x+1)(x-1)]
=3/(x-1)+3/(x+1)