(x-2)(x+1)分之3减去x-2分之1等于.
问题描述:
(x-2)(x+1)分之3减去x-2分之1等于.
答
3/[(x-2)(x+1)]-1/(x-2)
=[3-(x+1)]/[(x-2)(x+1)]
=-1/(x+1).