Вопрос:

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

Ответ:

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

\[= \frac{(x + 3)(x - 5)}{x + 3} =\]

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

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

\[D_{1} = 1 + 15 = 16\]

\[x_{1} = 1 + 4 = 5;\ \]

\[x_{2} = 1 - 4 = - 3.\]

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