ГДЗ по алгебре и начала математического анализа 10 класс Колягин Задание 384

\[\boxed{\mathbf{384}.}\]

\[x^{3} + ax^{2} + 5x - 3 = 0\]

\[P( - 3) = - 27 + 9a - 15 - 3 =\]

\[= 9a - 45 = 0\]

\[9a - 45 = 0\]

\[9a = 45\]

\[a = 5.\]

\[x^{3} + 5x^{2} + 5x - 3 = 0\]

\[P(x) =\]

\[= (x + 3)(x^{2} + 2x - 1) = 0\]

\[x^{2} + 2x - 1 = 0\]

\[D_{1} = 1 + 1 = 2\]

\[x = - 1 \pm \sqrt{2}.\]

\[Ответ:x = - 3;\ - 1 \pm \sqrt{2}.\]