当X趋向于0+时,lim(sinx/x)^(1/x)的极限

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当X趋向于0+时,lim(sinx/x)^(1/x)的极限当X趋向于0+时,lim(sinx/x)^(1/x)的极限当X趋向于0+时,lim(sinx/x)^(1/x)的极限取对数ln原式=lim(x

当X趋向于0+时,lim(sinx/x)^(1/x)的极限
当X趋向于0+时,lim(sinx/x)^(1/x)的极限

当X趋向于0+时,lim(sinx/x)^(1/x)的极限
取对数
ln原式=lim(x→0+)(ln(sinx)-lnx)/x
=lim(x→0+)(cosx/sinx-1/x)/1 (洛必达法则)
=lim(x→0+)(xcosx-sinx)/(xsinx)
=lim(x→0+)(xcosx-sinx)/x^2 (sinx~x)
=lim(x→0+)(cosx-xsinx-cosx)/(2x) (洛必达法则)
=lim(x→0+)-sinx/2
=0
所以原式=e^0=1

sinx=x-(1/6)x^3+o(x^3)
lim(sinx/x)^(1/x)
=lim(1-(x^2)/6)^(1/x)
=e^lim (ln(1-(x^2)/6))/x
=e^lim(-(x^2)/6)/x=e