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定义:若数列{an}对任意n∈N*,满足a(n+2)-a(n+1)/a(n+1)-an=k(k为常数)称数列{an}为等
题目内容:
定义:若数列{an}对任意n∈N*,满足a(n+2)-a(n+1)/a(n+1)-an=k(k为常数)称数列{an}为等差比数列.
(1)若数列{an}前n项和Sn=3(an-2),qiu {an}的通项公式,并判断该数列是否为等差比数列;
(2)若数列{an}为等差数列,是判断{an}是否一定为等差比数列,并说明理由;
(3)若数列{an}为等差比数列,定义中常数k=2,a2=3,a1=1,数列{(2n-1)/(an+1)}的前n项和为Tn,求证:Tn<3.
定义:若数列{an}对任意n∈N*,满足a(n+2)-a(n+1)/a(n+1)-an=k(k为常数)称数列{an}为等差比数列.
(1)若数列{an}前n项和Sn=3(an-2),qiu {an}的通项公式,并判断该数列是否为等差比数列;
(2)若数列{an}为等差数列,是判断{an}是否一定为等差比数列,并说明理由;
(3)若数列{an}为等差比数列,定义中常数k=2,a2=3,a1=1,数列{(2n-1)/(an+1)}的前n项和为Tn,求证:Tn<3.
(1)若数列{an}前n项和Sn=3(an-2),qiu {an}的通项公式,并判断该数列是否为等差比数列;
(2)若数列{an}为等差数列,是判断{an}是否一定为等差比数列,并说明理由;
(3)若数列{an}为等差比数列,定义中常数k=2,a2=3,a1=1,数列{(2n-1)/(an+1)}的前n项和为Tn,求证:Tn<3.
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