Решебник по алгебре 8 класс Мерзляк Задание 202

\[\boxed{\text{202\ (202).\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]

\[В\ данном\ случае\ выражение\ \]

\[не\ будет\ иметь\ смысла,\ если\]

\[знаменатель\ равен\ нулю.\]

\[1)\ \frac{6}{3x - 9}\]

\[3x - 9 = 0\]

\[3x = 9\]

\[x = 3\]

\[Ответ:при\ x = 3.\]

\[2)\ \frac{x^{2} + 1}{x^{2} - 1}\]

\[\frac{x^{2} + 1}{(x - 1)(x + 1)}\]

\[(x - 1)(x + 1) = 0\]

\[x = 1;\ \ \ \ x = - 1\]

\[Ответ:при\ x = 1\ и\ x = - 1.\]

\[3)\ \frac{x + 4}{3x^{2} + 12x}\]

\[3x^{2} + 12x = 0\]

\[3x(x + 4) = 0\]

\[3x = 0;\ \ \ \ \ \ x + 4 = 0\]

\[x = 0\ \ \ \ \ \ \ \ \ \ x = - 4\]

\[Ответ:при\ x = 0;\ \ x = - 4.\]

\[4)\ \frac{8}{x + 7} + \frac{4}{x - 2}\]

\[x + 7 = 0\ \ \ \ \ \ \ \ \ \ \ \ x - 2 = 0\]

\[x = - 7\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ x = 2\]

\[Ответ:при\ x = - 7;\ \ x = 2.\]

\[5)\ \frac{x}{x^{2} - 10x + 25}\]

\[x^{2} - 10x + 25 = 0\]

\[(x - 5)^{2} = 0\]

\[x = 5\]

\[Ответ:при\ x = 5.\]

\[6)\ \frac{x + 2}{(x + 10)(x - 12)}\]

\[x + 10 = 0;\ \ \ \ \ \ x - 12 = 0\]

\[x = - 10\ \ \ \ \ \ \ \ \ \ \ \ x = 12.\]

\[Ответ:при\ x = - 10;\ x = 12.\]