组卷网>知识点选题>公式法求数列通项
显示答案
| 共计 589 道试题
1 . 已知等差数列eqId93e38ecd74a24cb59da79181b95bfd3a中,eqIdfa72853ae1c74d1b9e41c587aab2c7cb
(1)求数列eqId93e38ecd74a24cb59da79181b95bfd3a的通项公式eqIdef9cef8e6d054d8dac46b8cde14953ad
(2)求数列eqId93e38ecd74a24cb59da79181b95bfd3a的第eqId401586f7a7f248b7904a4cfeaa2ed2f0项,第eqId1c1b006090344679b56b4c75d395cd8e项.
2 . 已知eqId93e38ecd74a24cb59da79181b95bfd3a为等比数列,且eqId706d613e657942d59a57d8132ec5e767eqId6756c898217949d391d1088dfb7b47ae.
(1)若eqId784ba0d5ecad4143ba51b340c16ddf21,求eqId5f904d1376ac4de7a7d6cfea92ff6981
(2)设数列eqId93e38ecd74a24cb59da79181b95bfd3a的前eqId5f904d1376ac4de7a7d6cfea92ff6981项和为eqIddb5481de79c946c0a760143297d5eade.求eqIdb4de3265b5d64840ad8080068acf2dad.
3 . 设eqIddb5481de79c946c0a760143297d5eade是数列eqId93e38ecd74a24cb59da79181b95bfd3a的前eqId5f904d1376ac4de7a7d6cfea92ff6981项和,eqId77b3f6b9955e499dbdab033a38779496eqId61b8f8cf7484430b85dcea23a63e1d48,则下列说法正确的有(   )
A.数列eqId93e38ecd74a24cb59da79181b95bfd3a的前eqId5f904d1376ac4de7a7d6cfea92ff6981项和为eqIdb4d0489b1cdd4d9eae8fdd27e6fd782a
B.数列eqIda4a8f097158842c99246acee68ad20d3为递增数列
C.数列eqId93e38ecd74a24cb59da79181b95bfd3a的通项公式为eqIde58ff15611b848feb92245f5e48646db
D.数列eqId93e38ecd74a24cb59da79181b95bfd3a的最大项为eqId75691f28a5bb4c8287401017aa3a2d29
4 . 已知公差不为0的等差数列eqId93e38ecd74a24cb59da79181b95bfd3a满足eqId77b3f6b9955e499dbdab033a38779496,且eqId0509add794484602a2c710f41d9ddddceqIdd80748a60dc04eb5bc4556d4e5cad370eqId65c5c1b67a274367bbfb17cb99036171成等比数列.
(1)求数列eqId93e38ecd74a24cb59da79181b95bfd3a的通项公式;
(2)若eqIdda32f2b25cd34f2ca39b40b362248504,求数列eqId7463ac5c573d4f0fb0aa7dcc4e8eb2f4的前eqId5f904d1376ac4de7a7d6cfea92ff6981项和eqIddb5481de79c946c0a760143297d5eade.
解答题 | 较易(0.85) | 2021·海南高二期末
5 . 在正项等比数列eqId93e38ecd74a24cb59da79181b95bfd3a中,eqId77b3f6b9955e499dbdab033a38779496eqIdfdec914615cd463ba6625e48492168db.
(1)求eqId93e38ecd74a24cb59da79181b95bfd3a的公比eqIda5d0fc594d4048549d5bbda484fbecc8
(2)设eqId7f7ed998e3d24daa998d24c89cb2a532,求数列eqIdeeb4ca98872f4e6d91cea28f43fc0b63的前eqId5f904d1376ac4de7a7d6cfea92ff6981项和eqIddb5481de79c946c0a760143297d5eade.
6 . 已知数列eqId93e38ecd74a24cb59da79181b95bfd3a满足eqId933ce44ed8cd4677a9edd0f08f1cb9b5,且eqId77b3f6b9955e499dbdab033a38779496.
(1)求数列eqId93e38ecd74a24cb59da79181b95bfd3a的通项公式;
(2)记eqId8250ec7fb6ea4f6eb4f403e63a2ed486,求证:eqIda6cb995e0f9b402d8ffccb742362c7dc.
解答题 | 较易(0.85) | 2021·陕西高二期末(理)
7 . 在各项均为正整数的等差数列eqId93e38ecd74a24cb59da79181b95bfd3a中,eqIdf45ac1c939c34e0e96cc25d7db622c46,且eqId740b43396fbb4655b53141c6f479cb6c为小于10的质数.
(1)求eqId93e38ecd74a24cb59da79181b95bfd3a的通项公式;
(2)若eqId12444893a88e43fcb5d793f265b02503,求数列eqIdeeb4ca98872f4e6d91cea28f43fc0b63的前eqId5f904d1376ac4de7a7d6cfea92ff6981项和eqIddb5481de79c946c0a760143297d5eade.
填空题 | 容易(0.94) | 2021·北京高二期末
8 . 已知等差数列eqId93e38ecd74a24cb59da79181b95bfd3a中,eqIdc7110fdf2b1a434db3efff31be1de8c7eqId14b485f4f46a4188a26d8798aaf9b627,则eqIdec15b069a63a4c5fb3a6606336bb1b1a______________
9 . 已知数列eqId93e38ecd74a24cb59da79181b95bfd3a是公比不为eqId37705e1ef6a84bbdbe88433e75932cdf的等比数列,且eqId7499ab4f63ab487fa41cf969a9508262成等差数列.
(1)求eqIdef9cef8e6d054d8dac46b8cde14953ad
(2)设eqId647519d5028348c583eb7ac71a57f682,求数列的前eqId16915e0b1cb849dd911814a3ca35d611项的和eqId7775abca18094d5b875faa6c07f00e2a
10 . 已知数列{an}是公比不为1的等比数列,且a3 +a4 = 12,3a1,2a2a3成等差数列.
(1)求an
(2)设eqIdcff106f8def14a4eae6b35680f807e7f,求数列{bn}的前2n项的和S2n.
客服 视频 帮助 公众号 官方微信