試題分析:由題意
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點評:等差數(shù)列題目中常用到的性質:若
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則
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科目:高中數(shù)學
來源:不詳
題型:解答題
已知等差數(shù)列
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的前
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項和為
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,若
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,
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,求:
(1)數(shù)列
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的通項公式;
(2)
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.
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科目:高中數(shù)學
來源:不詳
題型:填空題
已知等差數(shù)列
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中,
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成等比數(shù)列,則
.
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科目:高中數(shù)學
來源:不詳
題型:單選題
已知數(shù)列
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,
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,
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,
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成等差數(shù)列,
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,
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,
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,
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,
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成等比數(shù)列,則
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的值為( )
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科目:高中數(shù)學
來源:不詳
題型:解答題
已知曲線
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:
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,數(shù)列
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的首項
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,且
當
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時,點
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恒在曲線
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上,數(shù)列{
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}滿足
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(1)試判斷數(shù)列
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是否是等差數(shù)列?并說明理由;
(2)求數(shù)列
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和
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的通項公式;
(3)設數(shù)列
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滿足
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,試比較數(shù)列
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的前
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項和
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與
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的大�。�
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科目:高中數(shù)學
來源:不詳
題型:解答題
已知函數(shù)
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.
(1)求:
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的值;
(2)類比等差數(shù)列的前
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項和公式的推導方法,求:
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的值.
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科目:高中數(shù)學
來源:不詳
題型:解答題
數(shù)列
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中,
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,
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,
(1)若
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為公差為11的等差數(shù)列,求
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;
(2)若
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是以
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為首項、公比為
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的等比數(shù)列,求
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的值,并證明對任意
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總有:
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科目:高中數(shù)學
來源:不詳
題型:解答題
觀察下列三角形數(shù)表
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記第
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行的第m個數(shù)為
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.
(Ⅰ)分別寫出
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,
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,
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值的大��;
(Ⅱ)歸納出
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的關系式,并求出
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關于n的函數(shù)表達式.
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