因?yàn)閿?shù)列
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滿足
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,那么可知
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,兩式作差可知得到
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,故答案為
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科目:高中數(shù)學(xué)
來源:不詳
題型:解答題
(本小題滿分12分)
已知點(diǎn)
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是區(qū)域
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,(
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)內(nèi)的點(diǎn),目標(biāo)函數(shù)
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,
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的最大值記作
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.若數(shù)列
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的前
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項(xiàng)和為
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,
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,且點(diǎn)(

)在直線
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上.
(Ⅰ)證明:數(shù)列
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為等比數(shù)列;
(Ⅱ)求數(shù)列

的前
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項(xiàng)和
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.
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科目:高中數(shù)學(xué)
來源:不詳
題型:填空題
已知數(shù)列
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的首項(xiàng)為

,且

,則這個(gè)數(shù)列的通項(xiàng)公式為___________
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科目:高中數(shù)學(xué)
來源:不詳
題型:解答題
(本題滿分10分)
已知
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是等差數(shù)列,

是各項(xiàng)為正數(shù)的等比數(shù)列,且

,
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,
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.
(Ⅰ)求
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和
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通項(xiàng)公式;
(Ⅱ)若
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,求數(shù)列
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的前
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項(xiàng)和
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.
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來源:不詳
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在數(shù)列
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中,
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,且對(duì)于任意正整數(shù)n,都有
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來源:不詳
題型:解答題
在數(shù)列{a
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n+1=
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(n∈N*).
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2, a
3, a
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n,并用數(shù)學(xué)歸納法證明;
(Ⅲ)若數(shù)列b
n=

,求數(shù)列{b
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科目:高中數(shù)學(xué)
來源:不詳
題型:單選題
已知數(shù)列

滿足
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
,則數(shù)列
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科目:高中數(shù)學(xué)
來源:不詳
題型:單選題
已知函數(shù)
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,且
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,則
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( )
A.0 | B. | C.100 | D.10200 |
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科目:高中數(shù)學(xué)
來源:不詳
題型:解答題
(本題滿分14分)
(理)已
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知數(shù)列{a
n}的前n項(xiàng)和
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,且
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=1,
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
.(I)求數(shù)列{a
n}的通項(xiàng)公式;
(II)已知定理:“若函數(shù)f(x)在區(qū)間D上是凹函數(shù),x>y(x,y∈D),且f’(x)存在,則有
< f’(x)”.若且函數(shù)y=x
n+1
在(0,+∞)上是凹函數(shù),試判斷b
n與b
n+1的大��;
(III)求證:≤b
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