Задача 19303 Lim(n+1)^3-(n-1)^3/(n+1)^2+(n-1)^2...

u89151178111

10.11.2017

Lim(n+1)^3-(n-1)^3/(n+1)^2+(n-1)^2

SOVA

10.11.2017

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(n+1)^3–(n–1)^3=n^3+3n^2+3n+1-n^3+3n^2-3n+1=6n^2+2
(n+1)^2+(n–1)^2=n^2+2n+1+n^2-2n+1=2n^2+2

lim(6n^2+2)/(2n^2+2)=3