(11·大连)如图3,直线a∥b,∠1=115°,则∠2=_________°.
(2+3)(2-3)等于________________.
如果+=2,那么x满足的条件是________________.
当1<x<3时,|1-x|+等于_________________
当x取_____________时,的值最小,最小值是____________;当x取___________时,2-的值最大,最大值是_____________.
当x为_____________时,有意义;当x<-1时,=__________________.