已知f(x)=根号下4+1/x2,数列{an}的前n项和为Sn,点Pn(an,1/an+1)(n属于N*)在曲线y=f(x)上,且a1=1,an>0.求a已知f(x)=根号下4+1/x2,数列{an}的前n项和为Sn,点Pn(an,1/an+1)(n属于N*)在曲线y=f(x)上,且a1=1,an>0.求an 通项
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![已知f(x)=根号下4+1/x2,数列{an}的前n项和为Sn,点Pn(an,1/an+1)(n属于N*)在曲线y=f(x)上,且a1=1,an>0.求a已知f(x)=根号下4+1/x2,数列{an}的前n项和为Sn,点Pn(an,1/an+1)(n属于N*)在曲线y=f(x)上,且a1=1,an>0.求an 通项](/uploads/image/z/5427714-66-4.jpg?t=%E5%B7%B2%E7%9F%A5f%28x%29%3D%E6%A0%B9%E5%8F%B7%E4%B8%8B4%2B1%2Fx2%2C%E6%95%B0%E5%88%97%7Ban%7D%E7%9A%84%E5%89%8Dn%E9%A1%B9%E5%92%8C%E4%B8%BASn%2C%E7%82%B9Pn%28an%2C1%2Fan%2B1%29%28n%E5%B1%9E%E4%BA%8EN%2A%29%E5%9C%A8%E6%9B%B2%E7%BA%BFy%3Df%28x%29%E4%B8%8A%2C%E4%B8%94a1%3D1%2Can%3E0.%E6%B1%82a%E5%B7%B2%E7%9F%A5f%28x%29%3D%E6%A0%B9%E5%8F%B7%E4%B8%8B4%2B1%2Fx2%2C%E6%95%B0%E5%88%97%7Ban%7D%E7%9A%84%E5%89%8Dn%E9%A1%B9%E5%92%8C%E4%B8%BASn%2C%E7%82%B9Pn%28an%2C1%2Fan%2B1%29%28n%E5%B1%9E%E4%BA%8EN%2A%29%E5%9C%A8%E6%9B%B2%E7%BA%BFy%3Df%28x%29%E4%B8%8A%EF%BC%8C%E4%B8%94a1%3D1%2Can%3E0.%E6%B1%82an+%E9%80%9A%E9%A1%B9)
已知f(x)=根号下4+1/x2,数列{an}的前n项和为Sn,点Pn(an,1/an+1)(n属于N*)在曲线y=f(x)上,且a1=1,an>0.求a已知f(x)=根号下4+1/x2,数列{an}的前n项和为Sn,点Pn(an,1/an+1)(n属于N*)在曲线y=f(x)上,且a1=1,an>0.求an 通项
已知f(x)=根号下4+1/x2,数列{an}的前n项和为Sn,点Pn(an,1/an+1)(n属于N*)在曲线y=f(x)上,且a1=1,an>0.求a
已知f(x)=根号下4+1/x2,数列{an}的前n项和为Sn,点Pn(an,1/an+1)(n属于N*)在曲线y=f(x)上,且a1=1,an>0.求an 通项
已知f(x)=根号下4+1/x2,数列{an}的前n项和为Sn,点Pn(an,1/an+1)(n属于N*)在曲线y=f(x)上,且a1=1,an>0.求a已知f(x)=根号下4+1/x2,数列{an}的前n项和为Sn,点Pn(an,1/an+1)(n属于N*)在曲线y=f(x)上,且a1=1,an>0.求an 通项
1/an+1=√(4+1/an^2)
a2=√5/5
1/(an+1)^2=4+1/an^2
1/(an+1)^2-1/an^2=4
所以Tn=1/(an+1)^2是等差数列
T1=5
Tn=5+(n-1)*4=1/(an+1)^2=4n+1
所以an+1=√[1/(4n+1)]
an=√[1/(4n-3)] (n>=1)
j
1/an+1=√(4+1/an^2)
a2=√5/5
1/(an+1)^2=4+1/an^2
1/(an+1)^2-1/an^2=4
所以Tn=1/(an+1)^2是等差数列
T1=5
Tn=5+(n-1)*4=1/(an+1)^2=4n+1
所以an+1=√[1/(4n+1)]
an=√[1/(4n-3)] (n>=1)