formules à savoir
ln(ab) = lna + lnb ln(1/b) = - lnb ;
ln(a/b) = lna - lnb; lnaⁿ = n lna ;
ln√a = lna½ = 1/2 lna
et les fondamentaux
ln 1 = 0 ln e = 1
f(e) = ln e / e
= 1/e
f(e²) = ln e² = 2 ln e = 2
f(1/e) = ln (1/e) = - ln e = - 1
f(√e) = ln √e = ln e½ = 1/2 ln e = 1/2
