Posted by ALISON on .
how do i find the exact value of s
[pie/2, pie]
sin s = radical2/ whole number 2
what is s in radians?
how do i figure this out without the use of a calculator. I drew the graph and located it in the second quadrant and i think the triangle is a 454590 but i don't how to find the radians for the sin of s.

Trig 
Reiny,
start with this equation:
π radians = 180°
now divide this by simple whole numbers
e.g.
divide by 2 > π/2 = 90°
divide by 3 > π/3 = 60°
divide by 4 > π/4 = 45°
divide by 5 > π/5 = 36
divide by 6 > π/6 = 30°
divide by 8 > π/8 = 22.5°
etc.
copy this chart into a handy place in your notebook.
you know that the sine is positive in the first and 2nd quadrant.
Since s of sin s in in the second quadrant,
s = π  π/4 = 3π/4 , (18045 = 135°)
check:
sin 3π/4 = .707106781... = √2/2