Вопрос:

Постройте график функции y=(x^2+2x-15)/(x-3).

Ответ:

\[y = \frac{x^{2} + 2x - 15}{x - 3} = \frac{(x - 3)(x + 5)}{x - 3} =\]

\[= x + 5;\ \ \ \ \ x \neq 3.\]

\[x^{2} + 2x - 15 = 0\]

\[x_{1} + x_{2} = - 2;\ \ \ \ x_{1} \cdot x_{2} = - 15\]

\[x_{1} = 3;\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ x_{2} = - 5\]

\[x^{2} + 2x - 15 = (x - 3)(x + 5).\]

\[y = x + 5;\ \ \ x \neq 3\]

\[x\] \[0\] \[2\]
\[y\] \[5\] \[7\]

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