因为根号袭笑2x-6有意义,故2x-6>=0.得弯逗x>=3于是x-1>0,3-x<0故拍闹含:原式=x-1-(x-3)=x-1+3-x=2
√蠢闹(2x-6)有宴铅意义=》2x-6>晌档好=0=>x>=3|X-1|-|3-x| =x-1-(x-3)=2