Q. 44 - Precalculus Enhanced with Graphing Utilities

Question

find the average rate of change of f from$0$ to$\frac{\mathrm{\pi }}{6}$

$f\left(x\right)=sec \left(2x\right)$

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Step-by-Step Solution

Answer

the average rate of change of $f\left(x\right)=sec \left(2x\right)$ from$0$ to$\frac{\mathrm{\pi }}{6}$is$\frac{6}{\mathrm{\pi }}$

Step 1. Given data

The given function is

$f\left(x\right)=sec \left(2x\right)$

The given range is$\left[a,b\right]=\left[0,\frac{\mathrm{\pi }}{6}\right]$

Step 2. average rate of change

The average rate of change f

$$\begin{gathered} \frac{f\left(b\right)-f\left(a\right)}{b-a}=\frac{sec \left(2b\right)-sec \left(2a\right)}{b-a} \\ =\frac{sec (2\times {\displaystyle \frac{\mathrm{\pi }}{6}})-sec (2\times 0)}{\frac{\mathrm{\pi }}{6}-0} \\ =\frac{sec \left({\displaystyle \frac{\mathrm{\pi }}{3}}\right)-sec \left(0\right)}{\frac{\mathrm{\pi }}{6}-0} \\ =\frac{2-1}{\frac{\mathrm{\pi }}{6}} \\ =\frac{6}{\mathrm{\pi }} \end{gathered}$$

So average rate of change is$\frac{6}{\mathrm{\pi }}$