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            • 1.
              中国古代词中,有一道“八子分绵”的数学名题:“九百九十六斤绵,赠分八子做盘缠,次第每人多十七,要将第八数来言”\(.\)题意是:把\(996\)斤绵分给\(8\)个儿子作盘缠,按照年龄从大到小的顺序依次分绵,年龄小的比年龄大的多\(17\)斤绵,那么第\(8\)个儿子分到的绵是\((\)  \()\)
              A.\(174\)斤
              B.\(184\)斤
              C.\(191\)斤
              D.\(201\)斤
            • 2.
              设公差小于\(0\)的等差数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),且\(S_{3}=11a_{6}\),则当\(S_{n}\)取得最大值时\(n\)的值为\((\)  \()\)
              A.\(6\)
              B.\(7\)
              C.\(8\)
              D.\(11\)
            • 3.
              等差数列\(\{a_{n}\}\)的各项均不为零,其前\(n\)项和为\(S_{n}\),若\( a_{ n+1 }^{ 2 }=a_{n+2}+a_{n}\),则\(S_{2n+1}=(\)  \()\)
              A.\(4n+2\)
              B.\(4n\)
              C.\(2n+1\)
              D.\(2n\)
            • 4.
              已知递增的等差数列\(\{a_{n}\}\)的前三项和为\(-6\),前三项积为\(10\),则前\(10\)项和\(S_{10}=\) ______ .
            • 5.
              等差数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),若\(S_{5}=25\),则\(a_{3}=\) ______ .
            • 6.
              等差数列\(\{a_{n}\}\)前\(n\)项和为\(S_{n}\),若\(a_{4}\),\(a_{10}\)是方程\(x^{2}-8x+1=0\)的两根,则\(S_{13}=(\)  \()\)
              A.\(58\)
              B.\(54\)
              C.\(56\)
              D.\(52\)
            • 7.
              设\(\{a_{n}\}\)是任意等差数列,它的前\(n\)项和、前\(2n\)项和与前\(4n\)项和分别为\(X\),\(Y\),\(Z\),则下列等式中恒成立的是\((\)  \()\)
              A.\(2X+Z=3Y\)
              B.\(4X+Z=4Y\)
              C.\(2X+3Z=7Y\)
              D.\(8X+Z=6Y\)
            • 8.
              在等差数列\(\{a_{n}\}\)中,若\( \dfrac {a_{9}}{a_{8}} < -1\),且它的前\(n\)项和\(S_{n}\)有最小值,则当\(S_{n} > 0\)时,\(n\)的最小值为\((\)  \()\)
              A.\(14\)
              B.\(15\)
              C.\(16\)
              D.\(17\)
            • 9.
              在等差数列\(\{a_{n}\}\)中,\(a_{10}= \dfrac {1}{2}a_{14}-6\),则数列\(\{a_{n}\}\)的前\(11\)项和等于\((\)  \()\)
              A.\(132\)
              B.\(66\)
              C.\(-132\)
              D.\(-66\)
            • 10.
              已知等比数列\(\{a_{n}\}\),等差数列\(\{b_{n}\}\),\(T_{n}\)是数列\(\{b_{n}\}\)的前\(n\)项和\(.\)若\(a_{3}⋅a_{11}=4a_{7}\),且\(b_{7}=a_{7}\),则\(a_{7}=\) ______ ,\(T_{13}=\) ______ .
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