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            • 1.

              给出下列四个关于数列命题:

              \((1)\)若\(\left\{ {{a}_{n}} \right\}\)是等差数列,则三点\(\left( 10,\dfrac{{{S}_{10}}}{10} \right)\)、\(\left( 100,\dfrac{{{S}_{100}}}{100} \right)\)、\(\left( 110,\dfrac{{{S}_{110}}}{110} \right)\)共线;

              \((2)\)若\(\left\{ {{a}_{n}} \right\}\)是等比数列,则\({{S}_{m}}\)、\({{S}_{2m}}-{{S}_{m}}\)、\({{S}_{3m}}-{{S}_{2m}}\) \((m\in {{N}^{*}})\)也是等比数列;

              \((3)\)等比数列\(\left\{ {{a}_{n}} \right\}\)的前\(n\)项和为\({{S}_{n}}\),若对任意的\(n\in {{N}^{*}}\),点\(\left(n,{S}_{n}\right) \)均在函数\(y={{b}^{x}}+r\) \((b\ne 0,b\ne {1}, b.r\)均为常数\()\)的图象上,则\(r\)的值为\(-{1}\).

              \((4)\)对于数列\(\left\{ {{a}_{n}} \right\}\),定义数列\(\left\{{a}_{n+1}-{a}_{n}\right\} \)为数列\(\left\{ {{a}_{n}} \right\}\)的“差数列”,若\({{a}_{{1}}}{=2}\),\(\left\{ {{a}_{n}} \right\}\)的“差数列”的通项为\({{{2}}^{n}}\),则数列\(\left\{ {{a}_{n}} \right\}\)的前\(n\)项和\({{S}_{n}}\) \(={{2}^{n+1}}-2\)

              其中正确命题的个数是\((\)      \()\)

              A.\(4\)   
              B.\(3\)   
              C.\(2\)   
              D.\(1\)
            • 2.

              已知数列\(\left\{ {{a}_{n}} \right\}\)满足:\({{a}_{1}}=1,{{a}_{n}} > 0\),\(a_{n+1}^{2}-a_{n}^{2}=1\left( n\in {{N}^{*}} \right)\),那么使\({{a}_{n}} < 5\)成立的\(n\)的最大值为(    )

              A.\(4\)
              B.\(5\)
              C.\(24\)
              D.\(25\)
            • 3. 已知数列{an}的通项公式an=3n+1,求证:数列{an}是等差数列.
            • 4.

              等差数列\(\{a_{n}\}\)中,\(a_{2}=4\),\(a_{4}+a_{7}=15\).

              \((1)\)求数列\(\{a_{n}\}\)的通项公式;

              \((2)\)设\(b_{n}={2}^{{a}_{n}-2} +n\),求\(b_{1}+b_{2}+b_{3}+…+b_{10}\)的值.

            • 5.
              已知\(\{a_{n}\}\)是递增的等差数列\(a_{3}= \dfrac {5}{2}\),且\(a_{2}a_{4}=6\).
              \((1)\)求\(\{a_{n}\}\)的首项\(a_{1}\)和公差\(d\);
              \((2)\)求\(\{a_{n}\}\)的通项和前\(n\)项和\(S_{n}\).
            • 6.

              \((1)\int _{0}^{1}( \sqrt{1-{x}^{2}}+x+{x}^{3})dx \) ______      

              \((2)\)求值:\( \dfrac{\cos 20^{\circ}}{\cos 35^{\circ} \sqrt{1-\sin 20^{\circ}}} \) \(=\) ______         

              \((3)\)已知\(m\),\(n\),\(p\)表示不重合的三条直线,\(α\),\(β\),\(γ\)表示不重合的三个平面\(.\)下列说法正确的是 ______       \(.(\)写出所有正确命题的序号\()\).
              \(①\)若\(m⊥p\),\(m/\!/n\),则\(n⊥p\);
              \(②\)若\(m/\!/β\),\(n/\!/β\),\(m⊂α\),\(n⊂α\),则\(α/\!/β\);
              \(③\)若\(α⊥γ\),\(β⊥γ\),\(α∩β=m\),则\(m⊥γ\);
              \(④\)若\(α/\!/β\),\(m⊂α\),\(n⊂β\),则\(m/\!/n\).

              \((4)\)设函数\(y=f(x)\)的定义域为\(D\),若对于任意\(x_{1}\),\(x_{2}∈D\),当\(x_{1}+x_{2}=2a\)时,恒有\(f(x_{1})+f(x_{2})=2b\),则称点\((a,b)\)为函数\(y=f(x)\)图象的对称中心,研究函数\(f(x)=x^{3}+\sin x+2\)的图象的某一个对称点,并利用对称中心的上述定义,可得到\(f(-1)+f(- \dfrac{9}{10})+⋯+f(0)+⋯+f( \dfrac{9}{10})+f(1)= \)___           

            • 7.

              已知数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),且\(1\),\(a_{n}\),\(S_{n}\)是等差数列.

              \((\)Ⅰ\()\)求数列\(\{a_{n}\}\)的通项公式;

              \((\)Ⅱ\()\)若\(b_{n}=\log _{2}a_{n}\),设\(c_{n}=a_{n}⋅b_{n}\),求数列\(\{c_{n}\}\)的前\(n\)项和为\(T_{n}\).

            • 8.

              设\({{S}_{n}}\)是等差数列\(\left\{ a{}_{n} \right\}\)的前\(n\)项和,若\( \dfrac{{a}_{5}}{{a}_{3}}= \dfrac{5}{9}, \)则\( \dfrac{{S}_{9}}{{S}_{5}} =(\)   \()\)

              A.\(1\)
              B.\(-1\)
              C.\(2\)
              D.\(\dfrac{1}{2}\)
            • 9.

              已知在等比数列\(\{{{a}_{n}}\}\)中,\({{a}_{1}}=1\),且\({{a}_{2}}\)是\({{a}_{1}}\)和\({{a}_{3}}-1\)的等差中项.

              \((1)\)求数列\(\{{{a}_{n}}\}\)的通项公式;

              \((2)\)若数列\(\{{{b}_{n}}\}\)满足\({{b}_{n}}=2n+{{a}_{n}}(n\in {{N}^{*}})\),求\(\{{{b}_{n}}\}\)的前\(n\)项和\({{S}_{n}}\).

            • 10.

              已知数列\(\left\{ {{a}_{n}} \right\}\),\({{a}_{n}} > 0\),其前\(n\)项和\({{S}_{n}}\)满足\({{S}_{n}}=2{{a}_{n}}-{{2}^{n+1}}\),其中\(n\in N*\).

              \((\)Ⅰ\()\)设\({{b}_{n}}=\dfrac{{{a}_{n}}}{{{2}^{n}}}\),证明:数列\(\left\{ {{b}_{n}} \right\}\)是等差数列;

              \((\)Ⅱ\()\)设\({{c}_{n}}={{b}_{n}}\cdot {{2}^{-n}}\),\({{T}_{n}}\)为数列\(\left\{ {{c}_{n}} \right\}\)的前\(n\)项和,求证:\({{T}_{n}} < 3\);

              \((\)Ⅲ\()\)设\({{d}_{n}}={{4}^{n}}+{{(-1)}^{n-1}}\lambda \cdot {{2}^{{{b}_{n}}}}(\lambda \)为非零整数,\(n\in N*)\),试确定\(\lambda \)的值,使得对任意\(n\in N*\),都有\({{d}_{n+1}} > {{d}_{n}}\)成立.

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