如图所示
(2)lim (1+2x)^(1/x)x→0=lim {(1+2x)^[1/(2x)]}²x→0=e²(4)lim (1- 1/x)^(kx)x→∞=lim {[1+1/(-x)]^(-x)}^(-k)x→∞=e^(-k)
