Đáp án + Giải thích các bước giải:

$\log_a x = b \Rightarrow x = a^b$

$\log_a a = 1$

$\log_a 1 = 0$

$a^{\log_a b} = b$

$\log_a a^b = b \log_a a = b$

$\log_a b + \log_a c = \log_a bc$

$\Rightarrow \log_a b_1 + \log_a b_2 + ... + \log_a b_n = \log_a b_1b_2...b_n$

$\log_a b - \log_a c = \log_a \dfrac{b}{c}$

$\log_a b^c = c \log_a b$

$\log_a b^{2k} = 2k \log_a |b| (k \in \mathbb{N})$

$\Rightarrow \log_a \sqrt[c]{b} = \dfrac{1}{c}\log_a b$

$\log_a b . \log_b c = \log_a c$

$\Rightarrow \log_b c = \dfrac{\log_a c}{\log_a b}$

$\log_a b = \dfrac{1}{\log_b a}$

$\log_a^b c = \dfrac{1}{b}\log_a c$

$\log a =\lg a = \log_{10} a$

$\ln a = \log_e a$