SOLUTION: Is it possible to find x here where both a and b are known? a = cos(x - b) I have looked through all the identities on Wikipedia but just keep going round in circles. :( If t

Algebra ->  Trigonometry-basics -> SOLUTION: Is it possible to find x here where both a and b are known? a = cos(x - b) I have looked through all the identities on Wikipedia but just keep going round in circles. :( If t      Log On


   

Question 336320: Is it possible to find x here where both a and b are known?
a = cos(x - b)
I have looked through all the identities on Wikipedia but just keep going round in circles. :( If this doesn't appear to be possible, I will explain the context behind it but I'll just keep the question short and simple for now. Thanks.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Simply take the arccosine of both sides to get %22%22%2B-arccos%28a%29=x-b. Notice how cos%2860%29=cos%28-60%29=1%2F2. So this is why the "plus/minus" is there.


Then add b to both sides and rearrange terms to get x=b%2B-arccos%28a%29