(a)[4]
In terms of $k$, determine the $x$-coordinates where a stationary point occurs.
(b)[3]
The function $f$ has a stationary value at $x = a$ and is given by $f(x) = 4(3x - 4)^{-1} + 3x$ for $x \geq \frac{3}{2}$. Find $a$ and decide what type of stationary value it is.
(c)[2]
The function $g$ is given by $g(x) = -(3x + 1)^{-1} + 3x$ for $x \geq 0$. State, with clear reasoning, whether $g$ is increasing, decreasing or neither.