Suppose $\displaystyle f(t) = \frac{3}{t^{2}}$.

(a) Using the definition of the derivative, calculate the derivative of $f$.
Derivative = $\displaystyle f'(t) = \lim_{h \to 0} \Bigg( \frac{f(t+h)-f(t)}{h} \Bigg) = \lim_{h \to 0} \Bigg($ $\Bigg) =$ .

(b) Find the values of the derivative at the specified points.
$f'(-3)$ =
$f'(1)$ =
$f'(\sqrt{5})$ =