已知数列{An}的前n项和Sn满足2Sn^2=2An*Sn-An (n大于等于2)且A1=2,求An和Sn.稍微有点步骤.让我看的懂.3Q
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/31 01:16:24
![已知数列{An}的前n项和Sn满足2Sn^2=2An*Sn-An (n大于等于2)且A1=2,求An和Sn.稍微有点步骤.让我看的懂.3Q](/uploads/image/z/2117797-61-7.jpg?t=%E5%B7%B2%E7%9F%A5%E6%95%B0%E5%88%97%7BAn%7D%E7%9A%84%E5%89%8Dn%E9%A1%B9%E5%92%8CSn%E6%BB%A1%E8%B6%B32Sn%5E2%3D2An%2ASn-An+%28n%E5%A4%A7%E4%BA%8E%E7%AD%89%E4%BA%8E2%29%E4%B8%94A1%3D2%2C%E6%B1%82An%E5%92%8CSn.%E7%A8%8D%E5%BE%AE%E6%9C%89%E7%82%B9%E6%AD%A5%E9%AA%A4.%E8%AE%A9%E6%88%91%E7%9C%8B%E7%9A%84%E6%87%82.3Q)
xPj@.c1 d %Bi"hZ-iCж
>@g_dn
;sp!;
lcPek5Ĵ~v %6}0l>9@!9d{kY~gk[+2
已知数列{An}的前n项和Sn满足2Sn^2=2An*Sn-An (n大于等于2)且A1=2,求An和Sn.稍微有点步骤.让我看的懂.3Q
已知数列{An}的前n项和Sn满足2Sn^2=2An*Sn-An (n大于等于2)且A1=2,求An和Sn.
稍微有点步骤.让我看的懂.3Q
已知数列{An}的前n项和Sn满足2Sn^2=2An*Sn-An (n大于等于2)且A1=2,求An和Sn.稍微有点步骤.让我看的懂.3Q
2Sn(Sn-An)=-An
2SnSn-1=Sn-1-Sn
1/Sn-1/Sn-1=2
{1/Sn}便是一个等差数列,其首项为1/S1=1/A1=1/2
得出的结果便是:
Sn=2/(4n-3)
An=2/(4n-3)-2/(4n-7)
希望对你有帮助
已知数列an的前n项和sn满足sn=n的平方+2n-1求an
已知数列{an}的前n项和为sn,且满足sn=n
已知数列an的前n项和sn与通项an满足a1=2,sn+1sn=an+1,求sn
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
数列an的前n项和Sn满足:Sn=2n-an 求通项公式
已知数列的前n项和sn满足2sn-3an+2n=0(n
已知数列{an}的前n项和为Sn,且满足an+2Sn*Sn-1=0,a1=1/2.求证:{1/Sn}是等差数列
已知数列{an}的前n项和Sn满足Sn=2/3an-1/3,且1
(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
已知数列An的前n项和Sn满足An+2Sn*Sn-1=0,n大于等于2,A1=1/2,求An.
已知数列{an}满足an=2n/3^n,求此数列的前n项和sn
已知数列{an}的前n项和为Sn,an+Sn=2,(n
已知数列{an}的前n项和为Sn,且满足Sn=2an-1(n属于正整数),求数列{an}的通项公式an
已知数列(an)的前n项和为Sn,满足an+Sn=2n,证明数列(an-2)为等比数列并求出an
已知数列{an}a1=2前n项和为Sn 且满足Sn Sn-1=3an 求数列{an}的通项公式an已知数列{an}a1=2前n项和为Sn 且满足Sn +Sn-1=3an 求数列{an}的通项公式an
已知数列{An}的前N项和为Sn ,a1=-2分之一,满足SN+SN分之一=AN-2 n大于等于2,求S5
已知数列{an}的前n项和为Sn,且满足Sn=2an-1,n为正整数,求数列{an}的通项公式anRT ,
已知数列{an}的前n项和为Sn,满足Sn=2an-2n,1.求数列an的通向公式2.