[latex]displaystyle oxed{lim_{n o infty}left(1+dfrac{1}{n}
ight)^n=e}[/latex]
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[latex]displaystyle lim_{n o infty}left(1-dfrac{1}{n^2}
ight)^n=\\ lim_{n o infty}left(left(1+left(-dfrac{1}{n^2}
ight)
ight)^{-n^2}
ight)^{- frac{1}{n}}=\\ lim_{n o infty}e^{- frac{1}{n}}=\\ 1[/latex]
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[latex]displaystyle lim_{n o infty}left(1-dfrac{3}{n}
ight)^n=\\ lim_{n o infty}left(left(1+left(-dfrac{3}{n}
ight)
ight)^{- frac{n}{3}}
ight)^{-3}=\\ e^{-3}=\\ dfrac{1}{e^3}[/latex]