You know and . From the identity , you also know and . Maybe can be represented using and so that you can compute using the info above?
Hello could someone please solve this question for me. I need to see the steps invloved as i am not really sure of what i am meant to be doing. Thankyou so somuch
Using the identity sin^2theta + cos^2theta=1 and the identities for cos(A+B) find:
cos 75degrees if cos 45degrees = .707, and cos 30degrees = 0.866