配套习题-错位相减法求和 -【青果学院】

本课配套习题挑战模式1/3

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单选题

难度系数：

1.若数列{b_n}的通项公式为b_n=n²•2ⁿ，则其前n项和T_n=（）

A: （n²-2n+3）•2ⁿ⁺¹

B: （n²-2n+3）•2ⁿ-6

C: （n²-2n+3）•2ⁿ⁺¹-6

D: （n²-2n+3）•2ⁿ⁺¹+6

提示1：IOWFiOWmgumimOiuvuS4remUmeS9jeebuOWHj+azle+8jOato+WlveaxguW+l1Q8c3ViPm48L3N1Yj49LVM8c3ViPm48L3N1Yj4rbjxzdXA+Mjwvc3VwPiYjODIyNjsyPHN1cD5uKzE8L3N1cD7ov5vogIzlvpfliLDnrZTmoYgu
答案：Qw==
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单选题

难度系数：

2.已知数列{a_n}的前n项和为s_n，且a_n=n•3ⁿ，则s_n为：（）

A:

B:

C:

D:

提示1：IOe7k+WQiOaVsOWIl+eahOmAmumhueeahOeJueeCue+8jOiAg+iZkeWIqeeUqOmUmeS9jeebuOWHj+axguWSjOaWueazleWNs+WPr+axguinow==
答案：QQ==
PGltZyB3aWR0aD00MTYgaGVpZ2h0PTE0MiBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzFFLzNGL3JCQUNGRk43VEFQQkVMcDBBQUFhUWhfa1diZzExOS5wbmciPg==

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单选题

难度系数：

3.

A:

B:

C:

D:

提示1：IDxpbWcgd2lkdGg9NTU0IGhlaWdodD0zNCBzcmM9Imh0dHBzOi8vcDEucWluZ2d1by5jb20vRzEvTTAwLzFFLzQwL3JCQUNGRk43VEZqeEhWaVdBQUFTcE05VHVWVTgxLmpwZWciPg==
答案：Qw==
PGltZyB3aWR0aD0zODMgaGVpZ2h0PTIxNSBzcmM9Imh0dHBzOi8vcDEucWluZ2d1by5jb20vRzEvTTAwLzVBLzNGL3JCQUNFMU43VEZpei02OU5BQUFrbU5id3hJczM5MC5wbmciPg==