lim1/n[1^2+(1+1/n)^2+(1+2/n)^2+.(1+(n+1)/n)^2]的值是多少?n趋向∞

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lim1/n[1^2+(1+1/n)^2+(1+2/n)^2+.(1+(n+1)/n)^2]的值是多少?n趋向∞

lim1/n[1^2+(1+1/n)^2+(1+2/n)^2+.(1+(n+1)/n)^2]的值是多少?n趋向∞
lim1/n[1^2+(1+1/n)^2+(1+2/n)^2+.(1+(n+1)/n)^2]的值是多少?
n趋向∞

lim1/n[1^2+(1+1/n)^2+(1+2/n)^2+.(1+(n+1)/n)^2]的值是多少?n趋向∞
[1+k/n]^2= 1+2k/n+k^2/n^2
lim(n->∞) [1^2+(1+1/n)^2+(1+2/n)^2+.(1+(n+1)/n)^2]/n
=lim(n->∞) [∑(k=0,n+1) [1+ k/n]^2]/n
=lim(n->∞) [∑(k=0,n+1) [1+2k/n +k^2/n^2]]/n
=lim(n->∞) [(n+2) + (n+1)(n+2)/n +[(n+1)(n+2)(2n+3)/6]/n^2]/n
=lim(n->∞) [(n+2)/n + (n+1)(n+2)/n^2 +[(n+1)(n+2)(2n+3)/(6n^3)]
=7/3