#### Problem 12E

12. (a) If $f(x)=\sqrt{3-5 x}$, use the definition of a derivative to find $f^{\prime}(x)$.

(b) Find the domains of $f$ and $f^{\prime}$.

(c) Graph $f$ and $f^{\prime}$ on a common screen. Compare the graphs to see whether your answer to part (a) is reasonable.