lim(x→0)(2-e^x)^(1/x)

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lim(x→0)(2-e^x)^(1/x)

lim(x→0)(2-e^x)^(1/x)
lim(x→0)(2-e^x)^(1/x)

lim(x→0)(2-e^x)^(1/x)
lim(x→0)(2-e^x)^(1/x)
=lim(x→0)(1+1-e^x)^[1/(1-e^x)]^[(1-e^x)/x]
=lim(x→0)e^[(1-e^x)/x]
=e^[lim(x→0)(1-e^x)/x]
=e^[lim(x→0)(-e^x)](洛必达法则)
=e^(-1)
=1/e

x->0,e^x-1->x, ln(1+x)->x
故lim (2-e^x)^(1/x)=lim e^[1/x*ln(2-e^x)]=lim e^[1/x*ln(1+1-e^x)]=lim e^[1/x*ln(1-x)]
=lim e^(1/x*-x)=1/e