数列an定义如下a1=根号2,an+1=根号(2-根号(4-an^2))求an的通项
来源:学生作业帮助网 编辑:作业帮 时间:2024/11/09 06:03:45
数列an定义如下a1=根号2,an+1=根号(2-根号(4-an^2))求an的通项
数列an定义如下a1=根号2,an+1=根号(2-根号(4-an^2))
求an的通项
数列an定义如下a1=根号2,an+1=根号(2-根号(4-an^2))求an的通项
令bn=an/2,则an=2bn,带入得
4b[n+1]²=2-√(4-4bn²)=2(1-√(1-bn²))
=>2b[n+1]²=1-√(1-bn²) 显然0≤bn≤1
∴可设bn=sinβn,0≤βn≤π/2∴得
2sin²β[n+1]=1-cosβn=2sin²(βn/2)
=>sin²β[n+1]=sin²(βn/2)
=>sinβ[n+1]=sin(βn/2)
=>β[n+1]=βn/2
而b1=a1/2=√2/2=sinπ/4,∴β1=π/4
∴βn=β1/2^(n-1)=π/2^(n+1),
∴an=2bn=2sinβn=2sin(π/2^(n+1))
数列an定义如下a1=根号2,an+1=根号(2-根号(4-an^2))求an的通项
数列{an} 定义如下,a1=2,an+1=an^2-an+1,求证1/a1+1/a2+1/a3+……+1/a2008
已知数列an满足a1=1,1/an+1=根号1/an^2+2,an>0,求an
数列an满足an+1=根号(an^2+1)+an,a1=a>0,求an通项公式
a1=根号2,an+1=根号(2+an),求证数列{an}收敛,并求其极限
已知数列{an}中,a1=2,an+1=(根号2
数列{An}满足a1=1/2,a1+a2+..+an=n方an,求an
数列an中,a1=3,an+1=an/2an+1,则an=?
已知数列{an}满足a1=1,1/an+1=根号1/an62+2,an>0,求an是根号【1/(an^2+2)]
(1/an)-an=2根号n,且an>0(1)求数列{an}的通项公式,(2)证明a1+a2+……+an<根号n
若an是正项数列根号a1 + 根号a2+ .+ 根号an=n^2+3n则 (a1)/2+(a2)/3+.(an)/(n+1)=多少?
数列an,a1=1,n>=2,an=(根号下sn +根号sn-1)/2,求数列根号sn为等差数列,及an通项
在数列{an}中,a1=3,(根号an)-(根号an-1)-(根号3)=0,( n大于等于2,n属于N),则an=?
已知数列an满足a1=0,an+1=an-根号3/根号3an+1,则a2012=
数列{an}满足a1=1,an+1*根号(1/an^2+4)=1,S2n+1-Sn
在数列an中,a1=2,a(n+1)=an/2+1/an,试证:根号2
已知数列{an}满足,a1=2,a(n+1)=3根号an,求通项an数列{an}满足:an>0,且根号下Sn=an+1/4,求通项an
对于数列{an},定义数列{an+1-an}为数列{an}的差数列,若a1=1,{an}的差数列的通项公式为3∧n,则数列{an}的通项公式an=