两等差数列an.bn前n项和之比Sn/Tn=4n+1/9n+2,求a20/b20

两等差数列an.bn前n项和之比Sn/Tn=4n+1/9n+2,求a20/b20 若两等差数列an,bn的前n项和的比sn:sn'=5n+3/2n+7,则a5:b5 两等差数列﹛an﹜﹛bn﹜前n项和之比为5n+3/2n+7.则an/bn的值为? 两等差数列{an}、{bn}的前n项和的比Sn/S’n=（5n+3）/（2n+7）求a5/b5的值 两个等差数列{an}、{bn}的前n项和Sn、Tn之间的关系为an/bn = S(2n-1) / T(2n-1). 一道数学等差数列的题目等差数列an的前n项和Sn bn的前n项和Tn Sn比Tn=2n/(3n+1) 那么an与bn的比值是 等差数列{an}的前n项和sn=an^2+bn+c,则c= 两等差数列{an}和{bn},前n项和分别为Sn,Tn且Sn/Tn=7n+2/n+3则a2+a20/b7+b15= 两等差数列﹛an﹜﹛bn﹜前n项和之比为5n+3/2n+7.则a5/b5的值为? 等差数列an,bn的前n项和的比为Sn:Sn''=5n+3:2n+7,则a5:b5=? 已知两个等差数列an,bn,它们的前n项和的比sn/sn'=n+3/n+1,则a10/b10=? 已知数列{an}的前n项和sn满足sn=an^2+bn,求证{an}是等差数列 （1）若两等差数列{an},{bn}的前n项和分别为An,Bn,满足An/Bn=（7n+1）/（4n+27）,则a11/b11的值为（ ）（2）已知等比数列｛an},首项为81,数列{bn}满足bn=log3（an）,其前n项和为Sn.①证明{bn}为等差数列； (1)已知数列an的前n项和为sn满足sn=an²+bn,求证an是等差数列(2)已知等差数列an的前n项和为sn,求证数列sn/n也成等差数列 设{an}是等差数列,an=2n-1,{bn}是等比数列,bn=2^(n-1)求｛an/bn｝前n项和Sn 已知Sn为等差数列An的前n项和,Bn=Sn/n(n属于正整数）,求证：数列Bn是等差数列 已知等差数列{an}的前n项和为Sn,如果Sn=(an+1/2)^2(n∈N+0,bn=(-1)^n*Sn已知等差数列{an}的前n项和Sn,如果Sn=(an+1/2)^2(n∈N+0,bn=(-1)^n*Sn,试求{bn}的前n项和Tn an等差数列,前n项和sn=n^2,设bn=an/(3^n),bn前n项和Tn,证明Tn