椭圆16x2+9y2=144的长轴长为 .
考点分析:
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函数y=2sinωx(ω>0)的最小正周期是π,则ω=
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对于函数f(x),若存在x
o∈R,使f(x
o)=x
o成立,则称x
o为f(x)的不动点.如果函数f(x)=
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(b,c∈N
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.
(1)试求函数f(x)的单调区间;
(2)已知各项不为零的数列{a
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n•f(
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)=1,求证:-
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<ln
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<-
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;
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,T
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n}的前n项和,求证:T
2009-1<ln2009<T
2008.
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已知函数f(x)=e
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(1)当k=0时,若函数
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的定义域是R,求实数m的取值范围;
(2)试判断当k>1时,函数f(x)在(k,2k)内是否存在零点.
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函数
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已知△ABC中,
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.
(I)求f(θ)关于θ的表达式;
(II)求f(θ)的值域.
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