SOLUTION: 3 sin 2pi/3 - 4 cos 5pi/2. 5pi/2 isn't on unit circle, so what would I do?

Question 415400: 3 sin 2pi/3 - 4 cos 5pi/2.
5pi/2 isn't on unit circle, so what would I do?
Answer by Edwin McCravy(20060) (Show Source): You can put this solution on YOUR website!


Yes  is on the unit circle, because you can make more 
than just one lap around the unit circle. One lap around the 
unit circle is considered to be an angle of .  So you 
subtract  from , and that will be in the
same position on the unit circle, since it is exactly one lap
around the unit circle less.  So 



So  has the same trig functions as   

Therefore 



becomes









Edwin

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