Answer
In both cases (a. and b.):
$t^{\prime}(x)=\displaystyle \frac{1}{3}$
Work Step by Step
a.
$ t(x)=\displaystyle \frac{x}{3}=\frac{1}{3}\cdot x\qquad$ (constant multiple)
$t^{\prime}(x)=\displaystyle \frac{1}{3}(1)=\frac{1}{3}$
b.
$u(x)=x ,\displaystyle \ \ \ v(x)=3,\ \ \ s(x)=\frac{u(x)}{v(x)}$
$u^{\prime}(x)=1,\ \ \ v^{\prime}(x)=0$
Quotient Rule:
$t^{\prime}(x)=\displaystyle \frac{u^{\prime}(x)v(x)-u(x)v^{\prime}(x)}{[v(x)]^{2}}=$
$= \displaystyle \frac{1\cdot 3-0(x)}{3^{2}}=\frac{3}{9}=\frac{1}{3}$