SOLUTION: cos(pi/4)+cos(3pi/4)

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Question 372823: cos(pi/4)+cos(3pi/4)
Answer by nyc_function(2741)   (Show Source): You can put this solution on YOUR website!
cos(pi/4)+cos(3pi/4)=

Adding the numerators we get 4pi.

Then cos4pi/4 = cospi

Done!

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