已知等差数列{an}满足:a3=7,a5+a7=26,{an}的前n项和为Sn.求an及Sn;令bn=一除以an的平方减
已知等差数列{an}满足:a3=7,a5+a7=26,{an}的前n项和为Sn.求an及Sn;令bn=一除以an的平方减
已知等差数列{an}满足:a3=7,a5+a7=26,{an}的前n项和为Sn.求an及Sn.
已知等差数列{an}满足:a3=7,a5+a7=26.{an}的前n项和为Sn.(1)求an及Sn; (2)令bn=1/
已知等差数列{an}满足a3=7,a5+a7=26{an}的前n项和为Sn求a4及Sn
已知等差数列{an}满足∶a3=7,a5+a7=26,{an}的前几项和为sn令bn=2的n次方乘an,求数列前n项和T
等差数列{an}满足:a3=7.a5+a7=26.{an}的前n项和为sn.令bn=1/an^-1(1)求an及sn(2
已知等差数列an满足a3=7,a5+a7=26,an的前n项和为sn.1.求an和sn
已知等差数列{an}满足:a3=7,a5+a7=26.{an}的前n项和为Sn.求令bn=1/(an)^2-1,求{bn
已知等差数列【an】满足:a3=7,a5+a7=26.【an】的前n项和为Sn.(1)求a4及Sn;
已知等差数列{An}满足:a3=7 ,a5+a7=26 ,{An}的前n项和为Sn
已知等差数列{an}满足:a3=7,a5+a7 =26,an的前n项和为sn.
已知等差数列{an}满足:a3=7,a5+a7=26,{an}的前n项和为Sn.令bn=1/(an)^2-1(n∈N*)