Нужна помощь с логарифмами, объясните как решить

A)
$log_{2}x\ \textgreater \ 2 \\ x\ \textgreater \ 0 \\ log_{2}x\ \textgreater \ log_{2}2^2 \\ x\ \textgreater \ 2^2 \\ x\ \textgreater \ 4$
x∈(4; +∞) (1)
A - 1

Б)
$log_{2}x\ \textless \ -2 \\ x\ \textgreater \ 0 \\ log_{2}x\ \textless \ log_{2}2^{-2} \\ x\ \textless \ 2^{-2} \\ x\ \textless \ ( \frac{1}{2} )^2 \\ x\ \textless \ \frac{1}{4}$
x∈(0; 1/4) (4)
Б - 4

В)
$log_{2}x\ \textgreater \ -2 \\ x\ \textgreater \ 0 \\ log_{2}x\ \textgreater \ log_{2}2^{-2} \\ x\ \textgreater \ 2^{-2} \\ x\ \textgreater \ \frac{1}{4}$
x∈(1/4; +∞) (3)
В - 3

Г) $log_{2}x\ \textless \ 2 \\ x\ \textgreater \ 0 \\ log_{2}x\ \textless \ log_{2}2^2 \\ x\ \textless \ 2^2 \\ x\ \textless \ 4$
x∈(0; 4) (2)
Г - 2.