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科目:高中數(shù)學
來源:不詳
題型:解答題
(本小題滿分12分)
已知
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是公差不為零的等差數(shù)列,
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成等比數(shù)列.
(1)求數(shù)列

的通項; (2)求數(shù)列

的前n項和
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科目:高中數(shù)學
來源:不詳
題型:解答題
已知在遞增等差數(shù)列
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中,
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,
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成等比數(shù)列,數(shù)列
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的前n項和為
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,且
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.
(1)求數(shù)列
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、
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的通項公式;(2)設
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,求數(shù)列
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的前
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和
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.
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科目:高中數(shù)學
來源:不詳
題型:解答題
在等差數(shù)列
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中,
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,前
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項和
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滿足條件
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.
(Ⅰ)求數(shù)列

的通項公式;
(Ⅱ)記
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,求數(shù)列
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的前
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項和
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.
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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{a
n}的通項公式為
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,則數(shù)列{a
n}
A.有最大項,沒有最小項 | B.有最小項,沒有最大項 |
C.既有最大項又有最小項 | D.既沒有最大項也沒有最小項 |
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科目:高中數(shù)學
來源:不詳
題型:填空題
兩個等差數(shù)列
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前
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項和分別為
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,
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,則
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=_____.
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科目:高中數(shù)學
來源:不詳
題型:解答題
已知等比數(shù)列
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的前
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項和為
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,且
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是
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與2的等差中項,等差數(shù)列
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中,
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,點
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在直線
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上.
⑴求
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和
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的值;
⑵求數(shù)列

的通項
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和
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;
⑶ 設
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,求數(shù)列
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的前n項和
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.
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科目:高中數(shù)學
來源:不詳
題型:解答題
已知數(shù)列
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中各項均為正數(shù),
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是數(shù)列

的前

項和,且

.
(1)求數(shù)列

的通項公式
(2)對
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,試比較
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與
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的大小.
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科目:高中數(shù)學
來源:不詳
題型:單選題
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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,則
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的值是( �。�
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