问题标题:
【设数列an,bn分别满足a1*a2*a3...*an=1*2*3*4...*n,b1+b2+b3+...bn=an^2,n属于N+a1*a2*a3...*an=1*2*3*4...*n,b1+b2+b3+...bn=an^2,n属于N+1)求数列an和bn的通项公式】
问题描述:

设数列an,bn分别满足a1*a2*a3...*an=1*2*3*4...*n,b1+b2+b3+...bn=an^2,n属于N+

a1*a2*a3...*an=1*2*3*4...*n,b1+b2+b3+...bn=an^2,n属于N+

1)求数列an和bn的通项公式

陶少国回答:
  a1*a2*a3...*an*a(n+1)=1*2*3*4...*n*(n+1)   a1*a2*a3...*an=1*2*3*4...*n   两式相除   =>a1=1,a(n+1)=n+1=>an=n   b1+b2+b3+...bn=an^2=n^2   b1+b2+b3+...bn+b(n+1)=a(n+1)^2=(n+1)^2   两式相减   =>b1=1,b(n+1)=(n+1)^2-n^2=2n+1   =>bn=2n-1
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