document.write( "Question 336320: Is it possible to find x here where both a and b are known?\r
\n" ); document.write( "\n" ); document.write( "a = cos(x - b)\r
\n" ); document.write( "\n" ); document.write( "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. \n" ); document.write( "

Algebra.Com's Answer #241105 by jim_thompson5910(35256) $\"\"$ $\"About$

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. \r
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\n" ); document.write( "\n" ); document.write( "Then add b to both sides and rearrange terms to get $\"x=b%2B-arccos%28a%29\"$ \n" ); document.write( "

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