\[\boxed{\text{280\ (280).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[f(x) = x^{2},\]
\[D(f) = \lbrack a;2\rbrack;\ \text{\ \ }a < 2\]
\(\ \)
\[Если\ a < - 2:\ \]
\[f_{наиб} = f(a) = a^{2};\ \]
\[\ f_{наим} = f(0) = 0.\]
\[Если\ a = - 2:\ \]
\[f_{наиб} = f( - 2) = 4;\ \]
\[\ f_{наим} = f(0) = 0.\]
\[Если - 2 \leq a < 0:\ \]
\[f_{наиб} = f( - 2) = 4;\]
\[\text{\ \ }f_{наим} = f(0) = 0.\]
\[Если\ 0 < a \leq 2:\ \]
\[f_{наиб} = f(2) = 4;\ \ \]
\[f_{наим} = f(a) = a^{2}.\ \]