【单选题】函数f(x)= -cosx在[0,+∞)内 [ ]
【单选题】函数f(x)=2 x -cosx在[0,+∞)内( )
【多选题】在网络化的情况下,顾客概念及顾客行为发生了很大变化,下面选项中属于消费变化的为:()。
【简答题】函数f(x)= x -cosx在[0,+∞)内 ( ) A.没有零点 B.有且仅有一个零点 C.有且仅有两个零点 D.有无穷多个零点
【单选题】The writer thinks British drivers' behaviour to the misconduct of other drivers is too ______.
【单选题】My sister has been feeling ______ since she started her first job. She can’t sleep well.
【单选题】No sooner _____ to sleep than the telephone rang once more.