题型:选择题 题类:其他 难易度:中档
测年份:2018
已知\({{S}_{n}}\)为数列\(\left\{ {{a}_{n}} \right\}\)的前\(n\)项和,且\({lo}{{{g}}_{2}}\left( {{S}_{n}}+1 \right)=n+1\),则数列\(\left\{ {{a}_{n}} \right\}\)的通项公式为\((\) \()\)
题型:选择题 题类:其他 难易度:中档
测年份:2018
已知函数\(f(x)=x^{a}\)的图象过点\((4,2)\),令\(a_{n}= \dfrac{1}{f(n+1)+f(n)}\),\(n∈N^{*}\).记数列\(\{a\)\({\,\!}_{n}\)\(\}\)的前\(n\)项和为\(S\)\({\,\!}_{n}\),则\(S\)\({\,\!}_{2\;018}\)\(=(\) \()\)
题型:选择题 题类:其他 难易度:中档
测年份:2018
已知函数\({f}\left( {x} \right)={{{x}}^{2}}+{bx}\)的图象在点\({A}\left( 1,{f}\left( 1 \right) \right)\)处的切线\({l}\)与直线\(3{x}-{y}+2=0\)平行,若数列\(\left\{ \dfrac{1}{{f}\left( {n} \right)} \right\}\)的前\({n}\)项和为\({{{S}}_{{n}}}\),则\({{{S}}_{2017}}\)的值为( )
题型:选择题 题类:其他 难易度:中档
测年份:2018
设\(S_{n}\)是公差不为\(0\)的等差数列\(\left\{{a}_{n}\right\} \)的前\(n\)项和,\(S_{1}\),\(S_{2}\),\(S_{4}\)成等比数列,且\({{a}_{3}}=-\dfrac{5}{2},\)则数列\(\left\{ \dfrac{1}{\left(2n+1\right){a}_{n}}\right\} \)的前\(n\)项和为( )