SOLUTION: I am trying to use the addition and subtraction formulas to simplify sin(2pi-x). I am not sure where to begin.

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Question 69605: I am trying to use the addition and subtraction formulas to simplify sin(2pi-x). I am not sure where to begin.
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
I am trying to use the addition and subtraction 
formulas to simplify

+sin%282pi-+x%29+. 


I am not sure where to begin.

You have to know the formula

+sin%28A-B%29+=+sin%28A%29cos%28B%29-cos%28A%29sin%28B%29

Substitute 2pi for A and x for B

+sin%282pi-x%29+=+sin%282pi%29cos%28x%29-cos%282pi%29sin%28x%29

Now use the fact that 

sin%282pi%29+=+0 and cos%282pi%29+=+1

Substituting those:

+sin%282pi-x%29+=+%280%29cos%28x%29-%281%29sin%28x%29

%280%29cos%28x%29 is just 0 and we can erase the 1:

+sin%282pi-x%29+=+-sin%28x%29

Edwin