(nsin(1/n))^n^2在n趋近于无穷大时的极限

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(nsin(1/n))^n^2在n趋近于无穷大时的极限
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(nsin(1/n))^n^2在n趋近于无穷大时的极限
(nsin(1/n))^n^2在n趋近于无穷大时的极限

(nsin(1/n))^n^2在n趋近于无穷大时的极限
n→∞lim(nsin1/n)^n²
=n→∞lim[(sin1/n)/(1/n)]^n²
=x→0lim[(sinx)/x)]^(1/x)²
=x→0lime^ln[(sinx)/x)]^(1/x)²
=x→0lime^[(1/x)²]ln[(sinx)/x)]^(1/x)²
=x→0lime^{[(1/x)²]*ln[(sinx)/x)]}
=x→0lime^{ln[(sinx)/x)]/x²}
=x→0lime^{[(x/sinx)*(xcosx-sinx)/x²]/2x}(罗比塔法则)
=x→0lime^{[(x/x)*(xcosx-x)/x²]/2x}(等量替换)
=x→0lime^{[(cosx-1)/2x²]}
=x→0lime^{[(-sinx)/4x]}(罗比塔法则)
=x→0lime^{[(-x)/4x]}
=x→0lime^{[-1/4]}(等量替换)
=e^(-1/4)

(nsin1/n)^n^2
=[(1+nsin1/n-1)^(1/(nsin1/n-1)]^(nsin1/n-1)n^2
底数:[(1+nsin1/n-1)^(1/(nsin1/n-1)]趋于e
指数:(nsin1/n-1)n^2趋于0
原极限=1

原式=lime^ln[(sinx)/x)]^(1/x)²(x→0)
=lime^ln[(sinx)/x-1+1)]^(1/x)²(x→0)
=lime^[(sinx)/x-1)(1/x)²](x→0)(等量替换)
=lime^[(sinx-x)/x^3](x→0)(通分)
=lim...

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原式=lime^ln[(sinx)/x)]^(1/x)²(x→0)
=lime^ln[(sinx)/x-1+1)]^(1/x)²(x→0)
=lime^[(sinx)/x-1)(1/x)²](x→0)(等量替换)
=lime^[(sinx-x)/x^3](x→0)(通分)
=lime^[(cosx-1)/(3x^2)](x→0)(洛必达法则)
=lime^[(-x^2/2)/(3x^2)](x→0)(等量替换)
=e^(-1/6)

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