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            • 1.

              已知数列\(\{an\}\)的首项\({a}_{1}= \dfrac{3}{5},{a}_{n+1}= \dfrac{3{a}_{n}}{2{a}_{n}+1},n∈{N}^{*} \).

              \((1)\)求证:数列\(\{ \dfrac{1}{{a}_{n}}-1\} \)为等比数列;

              \((2)\)记\({S}_{n}= \dfrac{1}{{a}_{1}}+ \dfrac{1}{{a}_{2}}+...+ \dfrac{1}{{a}_{n}} \),若\(S_{n} < 101\),求最大正整数\(n\)的值;

                  \((3)\)是否存在互不相等的正整数\(m\),\(s\),\(n\),使\(m\),\(s\),\(n\)成等差数列,且\(a_{m}-1\),\(a_{s}-1\),\(a_{n}-1\)成等比数列?如果存在,请给予证明;如果不存在,请说明理由.

            • 2.

              设\(\{{{a}_{n}}\}\)是首项为\({{a}_{1}}\),公差为\(d\)的等差数列,\(\{{{b}_{n}}\}\)是首项为\({{b}_{1}}\),公比为\(q\)的等比数列.

              \((1)\)设\({{a}_{1}}=0,{{b}_{1}}=1,q=2\),若\(|{{a}_{n}}-{{b}_{n}}|\leqslant {{b}_{1}}\)对\(n=1,2,3,4\)均成立,求\(d\)的取值范围;

              \((2)\)若\({{a}_{1}}={{b}_{1}} > 0,m\in {{N}^{*}},q\in (1,\sqrt[m]{2}]\),证明:存在\(d\in R\),使得\(|{{a}_{n}}-{{b}_{n}}|\leqslant {{b}_{1}}\)对\(n=2,3,\cdots ,m+1\)均成立,并求\(d\)的取值范围\((\)用\({{b}_{1}},m,q\)表示\()\).

            • 3.

              已知数列\(\{a_{n}\}\)为等差数列,\(a_{1}=2\),\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),数列\(\{b_{n}\}\)为等比数列,且\(a_{1}b_{1}+a_{2}b_{2}+a_{3}b_{3}+…+a_{n}b_{n}=(n-1)⋅2^{n+2}+4\)对任意的\(n∈N*\)恒成立.

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

              \((2)\)是否存在非零整数\(λ\),使不等式\(\sin \dfrac{{a}_{n}π}{4} < \dfrac{1}{λ\left(1- \dfrac{1}{{a}_{1}}\right)\left(1- \dfrac{1}{{a}_{1}}\right)…\left(1- \dfrac{1}{{a}_{n}}\right) \sqrt{{a}_{n}+1}} \)对一切\(n∈N*\)都成立?若存在,求出\(λ\)的值;若不存在,说明理由.

              \((3)\)各项均为正整数的无穷等差数列\(\{c_{n}\}\),满足\(c_{39}=a_{1007}\),且存在正整数\(k\),使\(c_{1}\),\(c_{39}\),\(c_{k}\)成等比数列,若数列\(\{c_{n}\}\)的公差为\(d\),求\(d\)的所有可能取值之和.

            • 4. 设数列\(\{a_{n}\}\)满足\(a_{1}=0\)且\(\dfrac{1}{1-{{a}_{n+1}}}-\dfrac{1}{1-{{a}_{n}}}=1\).

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

              \((2)\)设\({{b}_{n}}=\dfrac{1-\sqrt{{{a}_{n+1}}}}{\sqrt{n}}\),记\({{S}_{n}}=\sum\limits_{k=1}^{n}{{{b}_{k}}}\),证明:\(S_{n} < 1\).

            • 5. 已知函数\(f(x)= \int _{ 0 }^{ x }(t^{2}-at-\cos t)dt\),\(g(x)=(a-x)\cos x\).
              \((\)Ⅰ\()\)当\(x\geqslant 0\)时,\(f(x)\geqslant g(x)\)恒成立,试求实数\(a\)的取值范围;
              \((\)Ⅱ\()\)若数列\(\{a_{n}\}\)满足:\(a_{0}= \dfrac { \sqrt {2}}{2}\),\(a_{n+1}= \dfrac { \sqrt {2}}{2} \sqrt {1- \sqrt {1-a_{n}^{2}}}(n=0,1,2,…)\),证明:\(a_{n} < \dfrac {π}{2^{n+2}}\).
            • 6.
              已知数列\(\{a_{n}\}\)是各项均不为零的等差数列,\(S_{n}\)为其前\(n\)项和,且\(a_{n}= \sqrt {S_{2n-1}}(n∈N^{*}).\)若不等式\( \dfrac {λ}{a_{n}}\leqslant \dfrac {n+8}{n}\)对任意\(n∈N^{*}\)恒成立,则实数\(λ\)的最大值为 ______ .
            • 7.

              已知首项为\(\dfrac{1}{3}\)的数列\(\{ a_{n}\}\)的前\(n\)项和为\(S_{n}\),定义在\({[}1{,+∞})\)上恒不为零的函数\(f(x)\),对任意的\(x\),\(y{∈}R\),都有\(f(x){⋅}f(y){=}f(x{+}y){.}\)若点\((n{,}a_{n})(n{∈}N{*})\)在函数\(f(x)\)的图象上,且不等式\(m^{2}{+}\dfrac{2m}{3}{ < }S_{n}\)对任意的\(n{∈}N{*}\)恒成立,则实数\(m\)的取值范围为______

            • 8. 在锐角\(\triangle ABC\)中,角\(A\)、\(B\)、\(C\)所对的边分别为\(a\),\(b\),\(c\),且\(A\)、\(B\)、\(C\)成等差数列,\(b= \sqrt {3}\),则\(\triangle ABC\)面积的取值范围是______.
            • 9. 各项均为正数的数列\(\{a_{n}\}\)中,前\(n\)项和\(S_{n}=( \dfrac {a_{n}+1}{2})^{2}\).
              \((1)\)求数列\(\{a_{n}\}\)的通项公式;
              \((2)\)若\( \dfrac {1}{a_{1}a_{2}}+ \dfrac {1}{a_{2}a_{3}}+…+ \dfrac {1}{a_{n}a_{n+1}} < k\)恒成立,求\(k\)的取值范围.
            • 10.
              数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),若数列\(\{a_{n}\}\)的各项按如下规律排列:\( \dfrac {1}{2}\),\( \dfrac {1}{3}\),\( \dfrac {2}{3}\),\( \dfrac {1}{4}\),\( \dfrac {2}{4}\),\( \dfrac {3}{4}\),\( \dfrac {1}{5}\),\( \dfrac {2}{5}\),\( \dfrac {3}{5}\),\( \dfrac {4}{5}…\),\( \dfrac {1}{n}\),\( \dfrac {2}{n}\),\(…\),\( \dfrac {n-1}{n}\),\(…\)有如下运算和结论:
              \(①a_{24}= \dfrac {3}{8}\);
              \(②\)数列\(a_{1}\),\(a_{2}+a_{3}\),\(a_{4}+a_{5}+a_{6}\),\(a_{7}+a_{8}+a_{9}+a_{10}\),\(…\)是等比数列;
              \(③\)数列\(a_{1}\),\(a_{2}+a_{3}\),\(a_{4}+a_{5}+a_{6}\),\(a_{7}+a_{8}+a_{9}+a_{10}\),\(…\)的前\(n\)项和为\(T_{n}= \dfrac {n^{2}+n}{4}\);
              \(④\)若存在正整数\(k\),使\(S_{k} < 10\),\(S_{k+1}\geqslant 10\),则\(a_{k}= \dfrac {5}{7}\).
              其中正确的结论是 ______ \(.(\)将你认为正确的结论序号都填上\()\)
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