SOLUTION: how do i find the exact value of cos 810 degrees?

Algebra ->  Trigonometry-basics -> SOLUTION: how do i find the exact value of cos 810 degrees?      Log On


   

Question 305188: how do i find the exact value of cos 810 degrees?
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Subtract 360º repeatedly until the angle is less than 360
810 - 360 = 450
450 - 360 = 90
cos(90) = 0
----------------