document.write( "Question 577832: What's the exact value of sin 13π/12 without using a calculator ? Can you please show all your work Thanks \n" ); document.write( "

Algebra.Com's Answer #370341 by Alan3354(69443) $\"\"$ $\"About$

You can put this solution on YOUR website!
13pi/12 = pi + pi/12 --> 3rd Quad
\n" ); document.write( "sin(13pi/12) = -sin(pi/12)
\n" ); document.write( "In degs, = -sin(15)
\n" ); document.write( "--------------
\n" ); document.write( "Use the half-angle formula
\n" ); document.write( "= -sin(30/2)
\n" ); document.write( "-sin(15) = -sin(30/2)
\n" ); document.write( "= $\"-sqrt%28%281+-+cos%2830%29%29%2F2%29\"$
\n" ); document.write( "= $\"-sqrt%28%281+-+sqrt%283%29%2F2%29%2F2%29\"$
\n" ); document.write( "= $\"-sqrt%282+-+sqrt%283%29%29%2F2\"$
\n" ); document.write( " \n" ); document.write( "

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