数列{An}中,A1=8,A4=,且满足:2A(n+2)-2A(n+1)+An=0数列{An}中,A1=8,A4=,且满足:2A(n+2)-2A(n+1)+An=0
来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/27 06:17:06
数列{An}中,A1=8,A4=,且满足:2A(n+2)-2A(n+1)+An=0数列{An}中,A1=8,A4=,且满足:2A(n+2)-2A(n+1)+An=0数列{An}中,A1=8,A4=,且
数列{An}中,A1=8,A4=,且满足:2A(n+2)-2A(n+1)+An=0数列{An}中,A1=8,A4=,且满足:2A(n+2)-2A(n+1)+An=0
数列{An}中,A1=8,A4=,且满足:2A(n+2)-2A(n+1)+An=0
数列{An}中,A1=8,A4=,且满足:2A(n+2)-2A(n+1)+An=0
数列{An}中,A1=8,A4=,且满足:2A(n+2)-2A(n+1)+An=0数列{An}中,A1=8,A4=,且满足:2A(n+2)-2A(n+1)+An=0
(1)a(n+2)-2a(n+1)+an=0
a(n+1)-a(n+1)=a(n+1)-an
所以数列an为等差数列
设an的公差为d
a4=a1+3d
d=-2
an=a1+(n-1)d
=8+2-2n
=10-2n
(2)bn=1/n(12-an)=1/n(2+2n)=2/(n+1)n
1/(n+1)n=1/n-1/(n+1)
Sn=b1+b2+b3+.+bn
=2/2*1+2/3*2+...+2/(n+1)n
=2[1-1/2+1/2-1/3+1/3-1/4+.+1/(n-1)-1/n+1/n-1/(n+1)]
=2[1-1/(n+1)]
因为1/(n+1)在定义域内为单调递减函数,当n=1时取最大值
所以当n=1时,Sn取最小值
2[1-1/2]
数列中,a1=8,a4=2,且满足an+2-2an+1+an=0.证明{an}是等差数列
)数列{An}中,A1=8,A4=2,且满足A(n+2)=2A(n+1)-.谢谢)数列{An}中,A1=8,A4=2,且满足A(n+2)=2A(n+1)-An,n属于N* 5 | 解决时间:2010-11-18 22:00 | 提问者:shuxuesg5 数列{An}中,A1=8,A4=2,且满足A(n+2)=2A(n+1)-An,n属于N* (1) 求
高一数列通项.数列{an}中 a1=2 ,a4=8且满足 a(n-2)=2a(n-1) - an (n∈N+)求数列{an}通项公式
数列{An}中,A1=8,A4=,且满足:2A(n+2)-2A(n+1)+An=0数列{An}中,A1=8,A4=,且满足:2A(n+2)-2A(n+1)+An=0
数列{an}中,a1=8,a4=2且满足a(n+2)=2a(n+1)-an,n属于N*数列{an}中,a1=8,a4=2且满足a(n+2)=2a(n+1)-an,n属于N*1.求数列{an}的通项公式2.设Sn=|a1|+|a2|+...+|an|,求Sn3.设bn=1/n(12-an)[n属于N*]是否存在最大的整数m,使得
数列{an}满足a1=2,且3an+1—an=0,则a4是多少?
数列{an}中a1=8,a4=2,且满足a(n+2)-2a(n+1)+an=0求通项公式(2)设Sn=‖a1‖+‖a2‖+```‖an‖求Sn
数列an中,a1=8,a4=2,且满足a(n+2)-2*a(n+1)+an=0(n∈N*).数列an中,a1=8,a4=2,且满足a(n+2)-2*a(n+1)+an=0(n∈N*)(1)求数列an的通项公式(2)设Sn=|a1|+|a2|+...+|an|,求Sn
1.数列{An}中,A1=8,A4=2且满足A(n+20)=2A(n+1)-An 问(1)求数列{An}的通项公式 (2)设Sn=|A1|+|A2|+……+|An|,求Sn2.数列{An}满足A1=2,对于任意的n∈N都有An>0,且(n+1)An^2+An×A(n+1)-nA(n+1)=0,又知数列{Bn}的通项公
已知递增数列{an}满足a1=1,(2an+1)=an+(an+2),且a1,a2,a4成等比数列.求an
已知等差数列an中,公差d>0,且满足a2*a3=45,a1+a4=14,求数列an的通项公式?
在等差数列an中,公差d>0.且满足a2·a3=45 a1+a4=14 求数列an的通项公式
已知等差数列an中.公差d>0.且满足a2*a3=45.a1+a4=14.求数列an的通项公式
已知数列{an}满足:a1=1,且an-an-1=2n,求(1)a2,a3,a4.(2)求数列{an}的通项an
已知等比数列(an)满足2a1+a3=3a2且a3+2是a2,a4的等差中项 求数列(an)的通项公式?
已知数列{an}中,a1=8,a4=2,且满足an+2-2an+1+an=0 (n∈N)求其前n项和Sn取到最大值时n的值
已知数列{an}满足a1=2且anan+1-2an=0球a2,a3,a4的值
已知数列{an}满足:a1=1,且an-a(n-1)=2n.求a2,a3,a4.求数列{an}通项an