Formulaire : mathématiques - Algèbre

Logarithmes

x = log_b( a ) <=> b^x = a (if a,b>0 and b ≠ 1)

log(a * b) = log(a) + log(b)

${log}\left( {\color{red} {a}} \times {\color{blue} {b}} \right) = {log}\left( {\color{red} {a}} \right) + {log}\left( {\color{blue} {b}} \right)$

log( a^b ) = b * log(a)

${log}\left( {\color{red} {a}}^{\color{blue} {b}} \right) = {\color{blue} {b}} \times {log}\left( {\color{red} {a}} \right)$

log( a/b ) = log(a) - log(b)

${log}\left( \frac{\color{red} {a}}{\color{blue} {b}} \right) = {log}\left( {\color{red} {a}} \right) - {log}\left( {\color{blue} {b}} \right)$