find the exact values of s in the given intervals that have the given circular function values.

Question

1. [pi/2,pi]; sin s=square root 2/2
2. [pi/2,pi]; cos s=-square root 3/2

Answer 1

these are simple angles
sin 45 degrees = (sqrt 2) /2
cos 30 deg = (sqrt 3)/2
But
Look, you need a calculator. Here is one.
For example for the angle whose sin is .75
type asin(.75) and click on the equal sign.
http://www.mathsisfun.com/scientific-calculator.html

Answer 2

Oh, did not notice between 90 and 180 degrees
180 - 45 = 135 degrees
180 - 30 = 150 degrees