\[\boxed{\text{1250.\ }\text{еуроки}\text{-}\text{ответы}\text{\ }\text{на}\text{\ }\text{пятёрку}}\]
\[y = \left\{ \begin{matrix} x^{- 1},\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ x < - \frac{1}{2} \\ 4x,\ \ - \frac{1}{2} \leq x \leq \frac{1}{2} \\ x^{- 1}\ ,\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ x > \frac{1}{2} \\ \end{matrix} \right.\ \Longrightarrow\]
\[\Longrightarrow y = \left\{ \begin{matrix} \frac{1}{x},\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ x < - \frac{1}{2} \\ 4x,\ \ - \frac{1}{2} \leq x \leq \frac{1}{2} \\ \frac{1}{x},\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ x > \frac{1}{2} \\ \end{matrix} \right.\ \]
\[x\] | \[- 1\] | \[- 2\] | \[- 3\] |
---|---|---|---|
\[y\] | \[- 1\] | \[- \frac{1}{2}\] | \[- \frac{1}{3}\] |
\[x\] | \[- \frac{1}{2}\] | \[0\] | \[\frac{1}{2}\] |
---|---|---|---|
\[y\] | \[- 2\] | \[0\] | \[2\] |
\[x\] | \[1\] | \[2\] | \[3\] |
---|---|---|---|
\[y\] | \[1\] | \[\frac{1}{2}\] | \[\frac{1}{3}\] |
\[\textbf{а)}\ y = 2:\ \ \ один\ корень.\]
\[\textbf{б)}\ y = \frac{1}{3}:\ \ \ два\ корня.\]
\[\textbf{в)}\ y = 0:\ \ \ \ один\ корень.\]
\[\textbf{г)}\ y = - 3:\ \ нет\ корней.\]