Question #b2b3e

2 Answers
Aug 23, 2017

1

Explanation:

We can add multiples of 2π to 5π2 to find coterminal angles.

5π2+2π=π2

This is located on the y-axis between Quadrant III and Quadrant IV.

The point on the unit circle at this location is (0,1), so

sin(5π2)=sin(π2)=1

Aug 23, 2017

-1

Explanation:

sin5π2= - sin 5π2

= -sin (2π+π2)

= - sin π2 = -1