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已知{an}是等差数列,其前n项和为Sn,{bn}是等比数列,且a1=b1=2,a4+b4...
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已知{a
n}是等差数列,其前n项和为S
n,{b
n}是等比数列,且a
1=b
1=2,a
4+b
4=27,S
4-b
4=10.
(1)求数列{a
n},{b
n}的通项公式;
(2)设T
n=
,若
恒成立,求实数c的最小值.
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已知{an}是等差数列,其前n项和为Sn,{bn}是等比数列,且a1=b1=2,a4+b4=27,s4-b4=10.
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