a) lim x→∞ ln(x) / x = lim x→∞ 1/x / 1 = 0
b) lim x→0+ x * ln(x) = lim x→0+ ln(x) / (1/x) = lim x→0+ 1/x / (-1/x^2) = lim x→0+ -x = 0
c) lim x→0+ x^x = lim x→0+ e^{x * lnx} = e^{0} = 1
d) lim x→∞ x^{1/x} = lim x→∞ e^{1/x * ln x} = e^0 = 1
e) lim n→∞ n(x^{1/n} - 1) = lim z→0 1/z * (x^z - 1) = lim z→0 (x^z - 1) / z = lim z→0 x^z * ln(x) / 1 = ln(x)