ГДЗ по алгебре 8 класс Макарычев ФГОС Задание 681

\[\boxed{\text{681\ (681).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]

\[4x^{2} + bx + c = 0,\]

\[\text{\ \ }x_{1} = 0,5,\ x_{2} = c\]

\[x^{2} + \frac{b}{4}x + \frac{c}{4} = 0\]

\[- \frac{b}{4} = 0,5 + 0\ \ \ \ \ | \cdot ( - 4)\]

\[b = - 2\]

\[Ответ:b = - 2,\ c = 0\text{.\ }\]

\[\boxed{\text{681.}\text{\ }\text{еуроки}\text{-}\text{ответы}\text{\ }\text{на}\text{\ }\text{пятёрку}}\]

\[\textbf{а)}\ y - x^{2} = 0\]

\[y = x^{2}\]

\[\textbf{б)}\ y - x^{3} = 0\]

\[y = x^{3}\]

\[\textbf{в)}\ 0,5xy + 1,5 = 0\ \ \ \]

\[0,5xy = - 1,5\]

\[xy = - 3\]

\[y = - \frac{3}{x}\]

\[\textbf{г)}\ y + x^{3} = 0\]

\[y = - x^{3}\]