已知函数f(x)=lnx-kx+1.
(1)求函数f(x)的单调区间;
(2)若f(x)≤0恒成立,试确定实数k的取值范围;
(3)证明:
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231546142650532/SYS201311012315461426505020_ST/0.png)
(n∈N
+,n>1).
考点分析:
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=(sinωx+cosωx,2sinωx),
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=(cosωx-sinωx,
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cosωx),(ω>0),若f(x)=
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f(x)=lg(a
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的最小值.
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