共50条信息
\(《\)九章算术\(》\)中有这样一段叙述:“今有良马与驽马发长安至齐,齐去长安三千里,良马初日行一百九十三里,日增一十三里;驽马初日行九十七里,日减半里,良马先至齐,复还迎驽马\(.\)”现有如下说法:\(①\)驽马第九日走了九十三里路;\(②\)良马五日共走了一千零九十五里路;\(③\)良马和驽马相遇时,良马走了二十一日\(.\)其中错误说法的个数为 ( )
已知在数列\(\{a_{n}\}\)中,\(a_{1}=-60\),\(a_{n+1}=a_{n}+3\),则\(|a_{1}|+|a_{2}|+|a_{3}|+…+|a_{30}|\)等于\((\) \()\)
数列\(\{\)\(a_{n}\)\(\}\)满足\(a\)\({\,\!}_{1}=19\),\(a_{n}\)\({\,\!}_{+1}=\)\(a_{n}\)\(-3(\)\(n\)\(∈N^{*})\),数列\(\{\)\(a_{n}\)\(\}\)的前\(n\)项和数值最大时,\(n\)的值为( )
如果\(a\)、\(x_{1}\)、\(x\)、\(b\)成等差数列,\(a\)、\(y_{1}\)、\(y_{2}\)、\(b\)成等比数列,那么\(\dfrac{{{x}_{1}}+{{x}_{2}}}{{{y}_{1}}{{y}_{2}}}\)等于\((\) \()\)
在数列\(\{ a_{n}\}\)中,\(a_{1}{=}3{,}2a_{n{+}1}{-}2a_{n}{=}1\),则\(a_{99}\)的值为\(({ })\)
.已知等差数列\(\{\)\(a_{n}\)\(\}\)的前\(n\)项和为\(S_{n}\),\(a\)\({\,\!}_{3}\)\(=\)\(5\),\(S\)\({\,\!}_{6}\)\(=\)\(36\),则\(a\)\({\,\!}_{6}\)\(=\)\((\) \()\)
进入组卷