9. The function \( f(x)=\frac{\sin \left(x^{2}-1\right)}{x(x+1)} \) (a) has one vertical asymptote (b) has two vertical asymptotes (c) is continuous on \( R \) (d) \( \lim _{x \rightarrow(-1)^{-}} f(x) \neq \lim _{x \rightarrow(-1)^{+}} f(x) \) (e) \( \lim _{x \rightarrow-1} f(x)=\infty \)

3. \( \lim _{x \rightarrow \infty} \frac{x-1}{2 x+5} \)

If the slope of the tangent to the curve: \( y=f(x) \) at any point on it equals \( 6 x+a \), whe \( a \) is constant if the equation of the tangent to the curve at the point \( (1,-1) \) is \( y=4- \) \( 5 x \), then the equation of the curve is ... \( \begin{array}{llll}\text { a) } y=3 x^{2}-4 & \text { b) } y=3 x^{2}-11 x+7 & \text { c) } y=3 x^{2}-4 x & \text { d) } y=3 x^{2}-x-3\end{array} \)

Show that \( \Gamma\left(\frac{1}{2}\right)=\sqrt{\pi} \)

3. \( \lim _{x \rightarrow \infty} \frac{x-1}{2 x+5} \)

(1) Find the value of: \( \quad \lim _{x \rightarrow 4} \frac{x^{3}-15 x-4}{x-4} \)