document.write( "Question 871595: cos-pi/12= \n" ); document.write( "

Algebra.Com's Answer #525761 by stanbon(75887) $\"\"$ $\"About$

You can put this solution on YOUR website!
cos(-pi/12) = cos(-15 deg( - cos(-30/2) = sqrt[(1-cos(30))/2]
\n" ); document.write( "====
\n" ); document.write( "= sqrt[(1-(sqrt(3)/2)/2]
\n" ); document.write( "----
\n" ); document.write( "= sqrt[(2-sqrt(3)/4] = (1/2)(2-sqrt(3)
\n" ); document.write( "---------
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
\n" ); document.write( "----------- \n" ); document.write( "

\n" );