\[y = x^{2} - 6x - 13\]
\[x_{0} = \frac{6}{2} = 3;\ \ y_{0} = 9 - 18 - 13 = - 22.\]
\[\lbrack - 2;7\rbrack:\]
\[y( - 2) = 4 + 12 - 13 = 3;\ \]
\[y(0) = - 13;\]
\[y(7) = 49 - 42 - 13 = - 6.\]
\[E(y) = \lbrack - 22;3\rbrack.\]