职教组卷基于海量职教高考试题库建立的在线组卷及学习系统
职教组卷
  • 题型:解答题 题类:模拟题 难易度:较易

    设\(\{a_{n}\}\)是等差数列,\(\{b_{n}\}\)是等比数列,公比大子\(0\),且\(a_{1}=b_{1}=3\),\(b_{2}=a_{3}\),\(b_{3}=4a_{2}+3.\)
    \((Ⅰ)\)求\(\{a_{n}\}\)和\(\{b_{n}\}\)的通项公式;
    \((Ⅱ)\)设数列\(\{c_{n}\}\)满足\(c_{n}=\begin{cases}{1,n\text{为奇数}}\\ {b_{\frac{n}{2}},n\text{为偶数}}\end{cases}\),求\(\sum\limits_{i=1}^{2n}a_{i}c_{i}.\)
  • 相关试卷