document.write( "Question 1193941: https://docs.google.com/document/d/1fwlRpNqz5l4Gbc2NvkH3RhcdsyxG3drAzyvOFfMwz48/edit?usp=sharing \n" ); document.write( "
Algebra.Com's Answer #826023 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
law of sines says:
\n" ); document.write( "sin(CAB) / 10 = sin(ABC) / 15
\n" ); document.write( "you are given sin(CAB) = sqrt(3)/3.
\n" ); document.write( "formula becomes:
\n" ); document.write( "(sqrt(3)/3) / 10 = sin(ABC) / 15
\n" ); document.write( "solve for sin(ABC) to get:
\n" ); document.write( "sin(ABC) = (15 * sqrt(3)/3) / 10 = .8660254038.
\n" ); document.write( "solve for ABC to get:
\n" ); document.write( "ABC = arcsin(.8660254038) = 60 degrees.
\n" ); document.write( "since ABC is also theta, then theta = 60 degrees.
\n" ); document.write( "since sin(CAB) = sqrt(3)/3, then:
\n" ); document.write( "CAB = arcsin(sqrt(3)/3) = 35.26438968 degrees.
\n" ); document.write( "2 * CAB = 70.52877937 degrees.
\n" ); document.write( "cos(2 * CAB) = cos(70.52877937) = .333333333... = 1/3.
\n" ); document.write( "let me know if you have any questions.
\n" ); document.write( "theo\r
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