document.write( "Question 151157: sin75 degree=? \n" ); document.write( "
Algebra.Com's Answer #111068 by jim_thompson5910(35256)\"\" \"About 
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\"sin%2875%29\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"sin%2845%2B30%29\" Rewrite 75 as 45+30. Take note that 45 and 30 are angles found on the unit circle.\r
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\n" ); document.write( "\n" ); document.write( "\"sin%2845%29cos%2830%29%2Bcos%2845%29sin%2830%29\" Expand the expression using the Sum-Difference identity\r
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\n" ); document.write( "\n" ); document.write( "\"%28sqrt%282%29%2F2%29%28sqrt%283%29%2F2%29%2B%28sqrt%282%29%2F2%29%281%2F2%29\" Evaluate \"sin%2845%29\" to get \"sqrt%282%29%2F2\". Evaluate \"cos%2830%29\" to get \"sqrt%283%29%2F2\". Evaluate \"cos%2845%29\" to get \"sqrt%282%29%2F2\". Evaluate \"sin%2830%29\" to get \"1%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%286%29%2F4%2Bsqrt%282%29%2F4\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"%28sqrt%286%29%2Bsqrt%282%29%29%2F4\" Add the fractions.\r
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\n" ); document.write( "\n" ); document.write( "So \"sin%2875%29=%28sqrt%286%29%2Bsqrt%282%29%29%2F4\"
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