a5a3a4的知识精选

设{an}是公比不为1的等比数列,其前n项和为Sn,且a5,a3,a4成等差数列.(1)求数列{an}的公比....
问题详情:设{an}是公比不为1的等比数列,其前n项和为Sn,且a5,a3,a4成等差数列.(1)求数列{an}的公比.(2)*:对任意k∈N*,Sk+2,Sk,Sk+1成等差数列.【回答】【解析】(1)设数列{an}的公比为q(q≠0,q≠1),由a5,a3,a4成等差数...
热门标签