Question

como calcular log x 1/16=2

Answer 1

$\mathtt{Log~_a~b = c} \\ \mathtt{Transforma ~em~\:} \\ \mathtt{b = a^c} \\ \\ \\ \mathtt{Log~_x~\frac{1}{16} = 2} \\ \\ \mathtt{\dfrac{1}{16} = x^2} \\ \\ \\ \mathtt{x^2 = \dfrac{1}{16}} \\ \\ \\ \mathtt{x = +-~\sqrt{\dfrac{1}{16}}} \\ \\ \\ \mathttt{x = -\dfrac{1}{4}~~~e~~\dfrac{1}{4}}$

Base de log não pode ser negativa, logo 

Resposta: 1/4