Question

Найдите область определения log(1-3x)

Answer 1

$1-3x\ \textgreater \ 0$
$-3x\ \textgreater \ -1$
$x\ \textless \ \frac{1}{3}$
$1-3x\ \textgreater \ 0$
$(-\infty; \frac{1}{3} )$
{${x|x\ \textless \ \frac{1}{3} }$}