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            • 1.
              如果等差数列\(\{a_{n}\}\)中,\(a_{3}+a_{4}+a_{5}=12\),那么\(a_{1}+a_{2}+…+a_{7}=(\)  \()\)
              A.\(14\)
              B.\(21\)
              C.\(28\)
              D.\(35\)
            • 2.
              等差数列\(\{a_{n}\}\)的前\(m\)项和为\(30\),前\(2m\)项和为\(100\),则它的前\(3m\)项和为\((\)  \()\)
              A.\(130\)
              B.\(170\)
              C.\(210\)
              D.\(260\)
            • 3.
              已知等差数列\(\{a_{n}\}\)的公差为\(2\),若\(a_{1}\),\(a_{3}\),\(a_{4}\)成等比数列,则\(a_{2}\)等于\((\)  \()\)
              A.\(-4\)
              B.\(-6\)
              C.\(-8\)
              D.\(-10\)
            • 4.
              已知数列\(\{a_{n}\}\)的前\(n\)项和\(S_{n}\),\(a_{1}=1\),\(a_{n+1}=a_{n}+ \dfrac {1}{2}(n∈N*)\),则\( \dfrac {S_{2017}}{2017}\)的值为\((\)  \()\)
              A.\(503\)
              B.\(504\)
              C.\(505\)
              D.\(506\)
            • 5. 已知4an+1-4an-9=0,则数列{an}是(  )
              A.公差为9的等差数列
              B.公差为的等差数列
              C.公差为4 的等差数列
              D.不是等差数列
            • 6. 如果一个数列的前5项分别是1,2,3,4,5,则下列说法正确的是(  )
              A.该数列一定是等差数列
              B.该数列一定不是等差数列
              C.该数列不一定是等差数列
              D.以上结论都不正确
            • 7. 已知数列{an}是各项为正数的等比数列,且a2=9,a4=81.
              (1)求数列{an}的通项公式an
              (2)若bn=log3an,求证:数列{bn}是等差数列.
            • 8.
              若等差数列\(\{a_{n}\}\)满足\(a_{1}+a_{2}+a_{2015}+a_{2016}=3\),则\(\{a_{n}\}\)的前\(2016\)项之和\(S_{2016}=(\)  \()\)
              A.\(1506\)
              B.\(1508\)
              C.\(1510\)
              D.\(1512\)
            • 9.
              已知数列\(\{a_{n}\}\)是等差数列,若\(a_{3}+a_{11}=24\),\(a_{4}=3\),则\(\{a_{n}\}\)的公差是\((\)  \()\)
              A.\(1\)
              B.\(3\)
              C.\(5\)
              D.\(6\)
            • 10.
              在等差数列\(\{a_{n}\}\)中,已知\(a_{4}+a_{8}=16\),则该数列前\(11\)项和\(S_{11}=(\)  \()\)
              A.\(58\)
              B.\(88\)
              C.\(143\)
              D.\(176\)
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