\[y = \sqrt{x - 2} - 3\]
\[x - 2 \geq 0\]
\[x \geq 2\]
\[D(y) = x \in \lbrack 2; + \infty).\]
\[y \geq - 3\]
\[E(y) = y \in \lbrack - 3;\ + \infty).\]