SOLUTION: I have to solve this function: f(-€/4)= cos2x
*let €= pi
So far I have gotten this far:
f(-€/4)= cos^2(-€/4) - sin^2(-€/4)
I figured that out using the double angle identit
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-> SOLUTION: I have to solve this function: f(-€/4)= cos2x
*let €= pi
So far I have gotten this far:
f(-€/4)= cos^2(-€/4) - sin^2(-€/4)
I figured that out using the double angle identit
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Question 770544: I have to solve this function: f(-€/4)= cos2x
*let €= pi
So far I have gotten this far:
f(-€/4)= cos^2(-€/4) - sin^2(-€/4)
I figured that out using the double angle identity. Now, I need to simplify it but I can't remember how to solve it without using a calculator. I am supposed to use only the unit circle and trig identities. Answer by solver91311(24713) (Show Source):
