Chapter 1.2, Problem 38E

For $f\left(x\right)$ and $g\left(x\right)$ given in the Problem 37 – 40, find

(a) $\left(f\circ g\right)\left(x\right)$

(b) $\left(g\circ f\right)\left(x\right)$

(c) $f\left(f\left(x\right)\right)$

(d) $f^2\left(x\right)=\left(f·f\right)\left(x\right)$

$f\left(x\right)=3x$

$g(x)=x^3-1$