①当a﹣1>0,即a>1时,x<a+1;
②当a﹣1<0,即a<1时,x>a+1;
③当a﹣1=0,即a=1时,不等式无解.
综上所述,
当a>1时,不等式的解集为{x|x<a+1};
当a<1时,不等式的解集为{x|x>a+1};
当a=1时,不等式的解集为∅.
—Yes. The last train for Guangzhou________at seven fifteen in the evening.
一Where are they from?
一Most of them from China. A small number of them from England.
若曲线f(x)=xsinx+1在x=π2处的切线与直线2x﹣ay+1=0互相垂直,则实数a等于( )