Radian and Degree Conversion

Throughout history, angles have ben measured in many different units. The most contemporary angles units are .....

• Degree $\left(\degree\right)$

• Radian $\left(rad\right)$
  

• Gradien $\left(grad\right)$

• Gradian $\left(grad\right)$

One radian is the angle made at the center of a circle by an arc whose length is equal to the radius of the circle.

• True

• False

 $72\degree$  is equal to ..... rad.

•  $\frac{3}{5}\pi$  

•  $\frac{8}{9}\pi$  

•  $\frac{2}{5}\pi$  

•  $\frac{4}{9}\pi$  

 $315\degree$  is equal to ..... rad.

•  $\frac{7}{4}\pi$  

•  $\frac{9}{5}\pi$  

•  $\frac{3}{4}\pi$  

•  $\frac{8}{5}\pi$  

 $\frac{\pi}{10\ }$  is equal to .....

•  $17\degree$  

•  $18\degree$  

•  $19\degree$  

•  $20\degree$  

 $\frac{4\pi}{9}$  is equal to .....

•  $50\degree$  

•  $60\degree$  

•  $70\degree$  

•  $80\degree$  

 $0.4\ rad$  is equal to .....

•  $60\degree$  

•  $71\degree$  

•  $72\degree$  

•  $65\degree$  

 $\sin\ \frac{\pi}{2}=.....$  

•  $-1$  

•  $1$  

•  $0$  

•  $\frac{1}{2}$  

 $\cos\ \frac{5\pi}{2}=\ .....$  

•  $\frac{1}{2}$  

•  $-\frac{1}{2}$  

•  $\frac{1}{2}\sqrt{2}$  

•  $-\frac{1}{2}\sqrt{2}$  

The length of QR is  $8.79\$ cm.

• True

• False