已知等差数列{An}的前n项和为Sn 且a3=5 S6=36
已知等差数列{An}的前n项和为Sn 且a3=5 S6=36
已知等差数列{An}的前n项和为Sn,且A3=5,S6=36.
已知等差数列{An}的前n项和为Sn,A3=5,S6=36 求An
已知等差数列﹛an﹜的前n项和为Sn,且a3=5,S6=36,bn=2an×2的an次方
已知等差数列{an}的前n项和为{Sn},已知a3=5.S6=36
已知{an}为等差数列,前n项和为Sn,S5=S6且a3=-6,(1)求数列{an}的通项公式
已知等差数列{An}的前n项和为Sn,且A3=5,S6=36.设bn=2^an+1/2,求数列bn的前n项和Tn
已知{an}是等差数列,前n项和是Sn,且a2+a7=9,S6=7a3.
已知{an}是等差数列,前n项和是Sn,且a2+a7=9,S6=7a3.(1)求数列{an}的通项公式..
已知等比数列{an}的公比为q,前n项和为Sn,且S3,S9,S6成等差数列,给出下列结论:①a3,a9,a6成等差数列
已知等差数列{An}的前n项和为Sn,且A3=6,S6=42.且满足A(n+2)=2A(n+1)-An
等差数列{an}的公差,d≠0,前n项和为Sn,且a1,a3,a9成等比数列,则S6/S10=