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问题 选择题
已知函数f′（x）是函数f（x）的导函数，g′（x）是函数g（x）的导函数，f(x)=
1
3
x3+x，g（x）=bx2-b2x，对于任意的a，b∈R，f′（a）与g′（a）的大小关系（　　）
A．f′（a）=g′（a）B．f′（a）＜g′（a）C．f′（a）＞g′（a）D．不能确定
答案

对f(x)=

1
3
x3+x求导，得

f′（x）=x2+1

对g（x）=bx2-b2x求导，得

g′（x）=2bx-b2

令f′（x）=g′（x），得

x2-2bx+b2+1=0

解得，△＜0，故在R内无解，即对于任意的a，b∈R，f′（a）与g′（a）没有交点

又因为g′（x）与y轴交点为-b2位于x轴下方，所以，

即对于任意的a，b∈R，f′（a）＞g′（a）

故答案选C

选择题

“可燃冰”的主要成分是一水合甲烷晶体(CH4·H2O)，请结合初中化学知识判断，下列说法正确的是[ ]

A．可燃冰能燃烧，说明水具有可燃性

B．可燃冰的发现为我国在全世界使用高效新能源开辟了广阔的前景

C．可燃冰由四种元素组成

D．可燃冰的主要成分是固态水
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填空题

The doctor-patient relationship is one of the (1) relationships in life, but many people say this relationship is beyond (2) . Can this relationship be saved The answer is (3) yes, because it must. And if that is lost, medicine becomes a technology and is (4) . In part the crisis in medicine began with doctors (5) themselves from patients.
The more critical work of a doctor happens in the taking of the human (6) . (7) is the most important and most difficult single transaction. The studies show that (8) of all the valuable information that leads to correct diagnosis comes from the history. Another (9) comes from the physical examination, 10% comes from simple (10) tests, and 5% comes from all the complex (11) . So listening is vital, because listening is not merely listening, but to establish a (12) .
But some doctors think listening is (13) . They like to use complex and costly (14) , and use (15) that create adverse reactions and require (16) . They don’t like to listen. Because there’s no premium on listening and that there’s no (17) for listening.
Even so, the doctor-patient relationship is not (18) saving. Because people may ask, what is good health And good health begins first and foremost with (19) . If you don’t care for a (20) , be somebody else, but don’t be a doctor!
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