"脾胃虚衰,元气不足"可导致发热,治当"甘温除热"的说法出于何书:
A.《河间六书》
B.《儒门事亲》
C.《格致余论》
D.《景岳全书》
E.《脾胃论》
参考答案:E
设偶函数f(x)在[0,+∞)上为增函数,且f(2)•f(4)<0,那么下列四个命题中一定正确的是( )
A.f(3)•f(5)≥0
B.函数在点(-4,f(-4))处的切线斜率k1<0
C.f(-3)>f(-5)
D.函数在点(4,f(4))处的切线斜率k2≥0
用limit 的短语或其适当形式完成句子。
1. One's energy is ____
2. ____ ( 没有止境) what you can do if you try.
3) We must ____ our weekly expenditure ____ ten pounds.
4)Only a ____ number of places are available.