SOLUTION: Cos 280� is equivalent to a)-sin 80� b)cos 10� c)cos 80� d) �cos 80� Answer: c (Just checking to make sure that I did my HW correct) Thanks

Question 388938: Cos 280� is equivalent to
a)-sin 80� b)cos 10� c)cos 80� d) �cos 80�
Answer: c (Just checking to make sure that I did my HW correct)
Thanks

Answer by ewatrrr(24785) (Show Source): You can put this solution on YOUR website!



Hi, 

Yes! on cos 280� = cos 80�... 

similar to example shown here for cos 300� = cos 60� 

(cosx,sinx)    

 

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