a1=1/2,3(1+an+1)/1-an=2(1+an)/1-an+1,anan+1=0,bn=an+1*2-an*2,求1)an,bn通项,2)证明bn中任意三项

来源：学生作业帮助网 编辑：六六作业网 时间：2024/11/27 16:47:26
a1=1/2,3(1+an+1)/1-an=2(1+an)/1-an+1,anan+1=0,bn=an+1*2-an*2,求1)an,bn通项,2)证明bn中任意三项a1=1/2,3(1+an+1)/

a1=1/2,3(1+an+1)/1-an=2(1+an)/1-an+1,anan+1=0,bn=an+1*2-an*2,求1)an,bn通项,2)证明bn中任意三项
a1=1/2,3(1+an+1)/1-an=2(1+an)/1-an+1,anan+1=0,bn=an+1*2-an*2,求1)an,bn通项,2)证明bn中任意三项

a1=1/2,3(1+an+1)/1-an=2(1+an)/1-an+1,anan+1=0,bn=an+1*2-an*2,求1)an,bn通项,2)证明bn中任意三项
1.
3(1-a²(n+1))=2(1-a²n)
(1-a²(n+1))/(1-a²n)=2/3
令tn=(1-a²n)
则tn为等比数列,首项,t1=3/4,公比为2/3
tn=3/4*(2/3)^(n-1)
(1-a²n)=3/4*(2/3)^(n-1)
a²n=1-3/4*(2/3)^(n-1)
an=+,-√[1-3/4*(2/3)^(n-1)]
an•（an+1）0
所以n为奇时,an>0,an=√[1-3/4*(2/3)^(n-1)]
n为偶时,an

数列{an}满足a1=a,an+1=1+1/an.若3/2 a(n+1)=2an/3an+4,a1=1/4,求an 数列{an},a1=3,an*a(n+1)=(1/2)^n,求an 数列[An]满足a1=2,a（n+1）=3an-2 求an 在数列{an}中.a1=3且a(n+1)=an^2,求an 已知数列｛an｝中,a(n+1)=an+2^n,a1=3,求an 2an+a(n-1)=3,a1=2 数列an中,a1=3,an+1=an/2an+1,则an=? 已知数列｛an｝中a1=1/2,a(n+1)=(2an)/(4an+3),求an. 已知数列an满足a1=1,a(n+1)=an/(3an+2),则an=? 1.a1=1 an=a1+2a2+.(n-1)an-1求an2.an+a（n+1）=1/2,a1=1,求an (1)数列{an}中,a1=1,a2=-3,a(n+1)=an+a(n+2),则a2005=____(2)已知数列｛an｝满足a1=1,a1×a2×a3…an=n^2,求an. a1=3 2an+1=an+1 A1=1,An+1=2An+3, 数列{An}满足a1=1/2,a1+a2+..+an=n方an,求an a1=3 an+1=2an-4 1、在数列{an}中,a1=1.a(n+1)=3an+2n+1.求an.2、在数列{an}中,a1=-1,a(n+1)=(3an-4)/[(an)-1].求an. 写出下列数列{an}的前5项 a1=1,a(n+1)=an+3 a1=2,a(n+1)=2an a1=3,a2=6,a(n+2)=a(n+1)-an