安徽安庆市第一中学等差数列最新高考试题精选
发布时间:2023-05-13 21:19:59
一、等差数列选择题1.已知等差数列an,其前n项的和为Sn,a3a4a5a6a720,则S9()A.24B.36C.48D.64
2.等差数列an中,已知a1a4a739,则a4()A.13B.14C.15D.16
3.设Sn是等差数列an的前n项和.若a1a4a76,则S7()A.10
B.8C.12D.14
4.在等差数列an中,a3a914,a23,则a10()A.11
B.10
C.6
D.3
n5.定义p1p2pn为n个正数p1,p2,,pn的“均倒数”,若已知数列an的前1()b9b10D.n项的“均倒数”为A.11a1,又bnn,则b1b2b2b322nB.81710
21C.11239
196.已知数列an是等差数列,其前n项和为Sn,若a4a54,则S8()A.16C.4B.-16D.-4
27.已知数列an