怕你看不懂,写得很详细。
简单计算一下,答案如图所示
=e^limln(arctanx/x)/x²
=e^lim(arctanx/x-1)/x²
=e^lim(arctanx-x)/x³
=e^lim(1/(1+x²)-1)/3x²
=e^lim-1/3(1+x²)
=e^(-1/3)
x->0
arctanx ~ x-(1/3)x^3
arctanx/x ~ 1-(1/3)x^2
lim(x->0) (arctanx/x) ^(1/x^2)
=lim(x->0) [1-(1/3)x^2 ] ^(1/x^2)
=e^(-1/3)