Chapter 3.2, Problem 44E

pose that $f\left(x\right)$, $g\left(x\right)$, and $h\left(x\right)$are functions such that $f\left(x\right)$is $\Theta \left(g\left(x\right)\right)$and $g\left(x\right)$is $\Theta \left(h\left(x\right)\right)$. Show that $f\left(x\right)$is $\Theta \left(h\left(x\right)\right)$.