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设等差数列{an}的前n项和为Sn,公比是正数的等比数列{bn}的前n项和为Tn,已知a1...
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设等差数列{a
n}的前n项和为S
n,公比是正数的等比数列{b
n}的前n项和为T
n,已知a
1=1,b
1=3,a
2+b
2=8,T
3-S
3=15
(Ⅰ)求{a
n},{b
n}的通项公式;
(Ⅱ)若数列{c
n}满足
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAQMAAAAgCAYAAAAWnh3nAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
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0gsCvg5gd3eTDkSQnHZzczx4aeM6vIUM9pONWF9+R4tFQDty3ha6tpjjzSYxi3sP512xMAzvT4t/
ncc9RbioXcSaQZqQ0VfI4JuOXHQeAuFazEEgJmaIZM6eyOXDudZliSIBs9jD6OC8+H2N4PY0IaeE
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uxJDHHr7IoVpuCr9B/Y5sTvKwIkFwk5OGDL5Vl8kAxI8iTA4V+/JNhagfJf6Vgu7AGXbm12iAJ/K
L2qufBOd0telCf4EwIRJISGcJE6+x44rwTVRBRiT6GgmI2d4oeISrTSQ0yvE/O36lh4C7Q42UqYh
xneyNsUJd19045cuXKKA3X51sub0hd8z2A3C9z22dfDjOMM6+0eIqeR/b8CqpAPl9xg8uNiUEg+m
Y8HJwCrA4AZVbvMpXCBpawPeWLXF4rnvlC4Ftdej3xkbkUHFm3BKrKsr1ZRy9kAGDPGotimlQ/U9
ViMycDsD5E04Id7Pqq3At+tFOXsgA0q70eDxzKZFY0kDjUA7MtCMnnoT/hlLuEVdO3hGzrobXjTO
Xys+eXtWeDy0KTkofQ7YjAzAb8KJcF6muiqrn5ZOzj7IgBMeT21K5FLdD9OIDCrehBNAXvMuIp6O
Us4eyIAPHs9tSuBQPzJEGzKoeROOBd6GtcFtqZoLJKRydkAGXPDA2BTrTz/UH04GiPfYZG/CC4bx
d7fjhyvwdIFMTgRWnHyPAx5Ym3LCk7sscDLgronIJwgIAigEhAxQ8ElnQaAfBIQM+rGlaCIIoBD4
B8Rut7EmlXCRAAAAAElFTkSuQmCC
)
对任意n∈N
*都成立;求证:数列{c
n}是等比数列.
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