Chapter C, Problem 4E

(a)

To determine

To calculate:

The value of following radian into degree

  $-\frac{7\pi }{2}$

Answer to Problem 4E

  $-\frac{7\pi }{2}$ into degree is $-630°$ .

Explanation of Solution

Given information:

  $-\frac{7\pi }{2}$

Formula Used:

The relation between the degree and radian is shown by below expression:

  $1rad=\frac{180°}{\pi }$

Calculation:

The given value of radian is $-\frac{7\pi }{2}$ .

Convert it into radian as:

  $\begin{array}{l}-\frac{7\pi }{2}=\frac{180°}{\pi }\times -\frac{7\pi }{2}\\ -\frac{7\pi }{2}=180\times -\frac{7}{2}\\ -\frac{7\pi }{2}=-90\times 7\\ -\frac{7\pi }{2}=-630°\end{array}$

(b)

To determine

To calculate:

The value of following radian into degree

  $\frac{8\pi }{3}$

Answer to Problem 4E

  $\frac{8\pi }{3}$ into degree is $67.5°$ .

Explanation of Solution

Given information:

  $\frac{8\pi }{3}$

Formula Used:

The relation between the degree and radian is shown by below expression:

  $1rad=\frac{180°}{\pi }$

Calculation:

The given value of radian is $\frac{8\pi }{3}$ .

Convert it into radian as:

  $\begin{array}{l}\frac{8\pi }{3}=\frac{180°}{\pi }\times \frac{8\pi }{3}\\ \frac{8\pi }{3}=180\times \frac{8}{3}\\ \frac{8\pi }{3}=60\times 8\\ \frac{8\pi }{3}=480°\end{array}$