优优班--学霸训练营 > 知识点挑题
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            • 1.
              已知数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),且满足\(S_{n}=(-1)^{n}\cdot a_{n}- \dfrac {1}{2^{n}}\),记\(b_{n}=8a_{2}\cdot 2^{n-1}\),若对任意的\(n∈N^{*}\),总有\(λb_{n}-1 > 0\)成立,则实数\(λ\)的取值范围为 ______ .
            • 2.
              已知数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),\(a_{1}=1\),且满足\(a_{n}a_{n+1}=2S_{n}\),数列\(\{b_{n}\}\)满足\(b_{1}=15\),\(b_{n+1}-b_{n}=2n\),则数列\(\{ \dfrac {b_{n}}{a_{n}}\}\)中第 ______ 项最小.
            • 3.
              设\(f(x)=f_{1}(x)= \dfrac {x}{1+x},f_{n}(x)=f_{n-1}[f(x)](n\geqslant 2,n∈N_{+})\),则\(f(1)+f(2)+…+f(n)+f_{1}(1)+f_{2}(1)+…+f_{n}(1)=\) ______ .
            • 4.
              已知数列\(\{ \sqrt {a_{n+1}}- \sqrt {a_{n}}\}\)是公差为\(2\)的等差数列,且\(a_{1}=1\),\(a_{3}=9\),则\(a_{n}=\) ______ .
            • 5. 在数列\(\{a_{n}\}\)中,若\(a_{4}=1\),\(a_{12}=5\),且任意连续三项的和都是\(15\),则\(a_{2018}=\)______.
            • 6.
              已知数列\(\{a_{n}\}\)满足\(a_{1}=1,|a_{n}-a_{n-3}|= \dfrac {1}{2^{n}}(n\geqslant 2,n∈N)\),且\(\{a_{2n-1}\}\)是递减数列,\(\{a_{2n}\}\)是递增数列,则\(5-6a_{10}=\) ______ .
            • 7.
              设数列\(\{a_{n}\}\)的通项公式为\(a_{n}=n^{2}+bn\),若数列\(\{a_{n}\}\)是单调递增数列,则实数\(b\)的取值范围为 ______ .
            • 8.
              已知\(f(x)= \dfrac {1-x}{1+x}\),数列\(\{a_{n}\}\)满足\(a_{1}= \dfrac {1}{2}\),对于任意\(n∈N^{*}\)都满足\(a_{n+2}=f(a_{n})\),且\(a_{n} > 0\),若\(a_{20}=a_{18}\),则\(a_{2016}+a_{2017}\)的值为 ______ .
            • 9. 已知数列{an}的前n项和Sn=2an-2n+1,若不等式2n2-n-3<(5-λ)an对∀n∈N+恒成立,则整数λ的最大值为    
            • 10. 已知定义在R上的奇函数y=f(x)满足f(2+x)=f(2-x),当-2≤x<0时,f(x)=2x,若an=f(n)(n∈N*),则a2012=    
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