document.write( "Question 1207451: If sin3y = cos2y and 0°≤y≤90°, find the values of y. \n" ); document.write( "
Algebra.Com's Answer #845322 by Edwin McCravy(20059)\"\" \"About 
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document.write( "sin(3y)=cos(2y),   \"0%5Eo%3C=y%3C=90%5Eo\"\r\n" );
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document.write( "For the case \r\n" );
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document.write( "\"cos%282y%29=cos%2890%5Eo-3y%2B360%5Eo%2An%29\"\r\n" );
document.write( "\"2y+=+90%5Eo-3y%2B360%5Eo%2An\"\r\n" );
document.write( "which simplifies to\r\n" );
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document.write( "\"5y=90%5Eo%2B360%5Eo%2An\"\r\n" );
document.write( "\"y=18%5Eo%2B72%5Eo%2An\"\r\n" );
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document.write( "This gives us the solutions 18o, 90o, for n=0 and n=1\r\n" );
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document.write( "However, this may not be all possible solutions \"0%5Eo%3C=y%3C=90%5Eo\"\r\n" );
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document.write( "We must also consider the case\r\n" );
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document.write( "\"cos%282y%29=cos%283y-90%5Eo%2B360%5Eo%2An%29\"\r\n" );
document.write( "\"2y+=+3y-90%5Eo%2B360%5Eo%2An\"\r\n" );
document.write( "which simplifies to\r\n" );
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document.write( "\"-y=-90%5Eo%2B360%5Eo%2An\"\r\n" );
document.write( "\"y=90%5Eo-360%5Eo%2An\"\r\n" );
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document.write( "We get only a repeat of the solution 90o for n=0 \r\n" );
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document.write( "18o, 90o are the only solutions \r\n" );
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document.write( "Edwin
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