\[\boxed{\text{91\ (91).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[y = - 2x^{2}\]
\[\textbf{а)}\ y( - 1,5) = - 2 \cdot ( - 1,5)^{2} =\]
\[= - 2 \cdot {1,5}^{2} = - 2 \cdot 2,25 = - 4,5;\]
\[y(0,6) = - 2 \cdot {0,6}^{2} = - 0,72;\]
\[y(1,5) = - 2 \cdot {1,5}^{2} = - 4,5.\]
\[\textbf{б)}\ y = - 1:\ \ \ \]
\[- 1 = - 2x^{2}\]
\[x^{2} = \frac{1}{2}\]
\[x = \pm \sqrt{\frac{1}{2}}.\]
\[y = - 3:\ \ \ \]
\[- 3 = - 2x^{2}\]
\[x^{2} = \frac{3}{2}\text{\ \ }\]
\[x = \pm \sqrt{\frac{3}{2}}.\]
\[y = - 4,5:\ \ \]
\[- 4,5 = - 2x^{2}\]
\[x^{2} = \frac{4,5}{2}\text{\ \ }\]
\[x = \pm \sqrt{2,25} = \pm 1,5.\]
\[\textbf{в)}\ Функция\ возрастает\ на\ \]
\[промежутке\ ( - \infty;0\rbrack\ и\ убывает\ \]
\[на\ промежутке\ \lbrack 0;\ + \infty).\]