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#### I'm super frustrated about this one problem in math, it's really difficult and it's hard to figure out where to start.

17 viewed last edited 4 years ago Isaac
-1
The long question and I can't find the answer, I need to know how to do it. Can someone explain to me how to do sin(6)cos(6)cos(6)(12) x 50 cos(5)cos(123), really frustrating and I need to know please help quick, and thorough explanation would be useful thank you! Mahesh Godavarti
-2

Shrek, can you check your question again and see if you wrote it out properly? Or you can simply attach a picture of the question. I will be able to help you better then.

Typically, these types of problems use the following identities:

1. 2 sin(A) cos(A) = sin(2A)
2. cos2(A) - sin2(A) = cos(2A)
3. sin(A) cos(B) + cos(A) sin(B) = sin(A + B)
4. cos(A) cos(B) - sin(A) sin(B) = cos(A + B)
5. 2 sin2(A) = 1 - cos(2A)
6. sin2(A) + cos2(A) = 1

We have to repeatedly apply these identities till we get a cos or sin that we know the answer to. E.g. cos(180), cos(60) etc.