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题型:解答题 题类:期中考试 难易度:中档
已知等差数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),且\(S_{2}=4\),\(S_{5}=25\),等比数列\(\{b_{n}\}\)中,\(b_{2}=3\),\(b_{3}=9\).
\((1)\)求数列\(\{a\)\(n\)\(\}\),\(\{b\)\(n\)\(\}\)的通项公式;
\((2)\)求数列\(\{a\)\({\,\!}_{n}-bn\)\(\}\)的前\(n\)项和\(T_{n}\).
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