数列

的前n项和

的通项公式为 ( )
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科目:高中数学
来源:不详
题型:解答题
等差数列
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的前
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项和为

,且

(1)求

的通项公式

;
(2)若数列

满足


的前

项和

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科目:高中数学
来源:不详
题型:单选题
在数列

中,

=1,

,则

的值为 ( )
A.99 | B.49 | C.102 | D.101 |
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科目:高中数学
来源:不详
题型:单选题
设

为等比数列

的前n项和,

,则

( )
A.—11 | B.—8 | C.5 | D.11 |
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科目:高中数学
来源:不详
题型:单选题
如果数列

满足

,

,且

(

≥2),则这个数列的第10项等于( )
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科目:高中数学
来源:不详
题型:单选题
已知等差数列

与等比数列

,满足

则

的
前5项和

( )
A.5 | B.10 | C.20 | D.40  |
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科目:高中数学
来源:不详
题型:单选题
若等差数列{
an}的公差为
d,且
a1+
a4=3,
a2+
a5=5,则
d的值为( )
A. 1 | B. 2 | C. 3 | D.4 |
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