4.下列函数中,在区间上为增函数的是( )
A. B. C. D.
3.已知向量a,b ,则向量a+b所在的直线可能为( )
A.轴 B.第一、三象限的角平分线
C.轴 D.第二、四象限的角平分线
2.复数的虚部是( )
1.集合,集合,则与的关系是( )
50.It’s ______ to borrow money from your mother to settle your debt to your uncle. That’s just robbing Peter to pay Paul.
A.ridiculous B. strange C. stubborn D. splendid
49.Everything works out well. ____, we are sure that the experiment will be completed on time.
A.Therefore B. While C. However D. Otherwise
48.Although my grandfather is in his eighties, he is still as ______ as a young man and hates sitting around doing
nothing all day.
A. enthusiastic B. automatic C. energetic D. innocent
47.He was robbed last night, but he didn’t have much on him then.
A.fortunately B.eventually C.certainly D.surprisingly
46.Letterboxes are much more ____ in the UK than in the US, where most people have a mailbox instead.
A. common B. normal C. ordinary D. usual
45.After I arrived at her house, she showed me into ____________.
A. a room cosy or little B. a little cosy room C. a cosy little room D. cosy little a room