document.write( "Question 1198695: Aplique a propriedade do logaritmo \r
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Algebra.Com's Answer #832329 by ikleyn(52800)\"\" \"About 
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document.write( "We start from this expression  \"log%282%2C%284x%5E2%29%29\".\r\n" );
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document.write( "In this expression, x can be any non-zero number, negative or positive.\r\n" );
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document.write( "In other words, the domain, where the expression is defined / (makes sense), \r\n" );
document.write( "is the set of all real non-zero numbers {R \ {0} }.\r\n" );
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document.write( "In this domain\r\n" );
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document.write( "    \"log%282%2C%284x%5E2%29%29\" = \"log%282%2C%284%29%29\" + \"log%282%2C%28x%5E2%29%29\" = \"2+%2B+log%282%2C%28x%5E2%29%29\".\r\n" );
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document.write( "Now,  \"log%282%2C+%28x%5E2%29%29\" = \"2%2Alog%282%2C%28abs%28x%29%29%29\"  is valid for all values of x in the domain, positive or negative,\r\n" );
document.write( "excluding the zero value of x.  Notice the absolute value sign under the logarithm.\r\n" );
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document.write( "Therefore, in the entire domain,  \"log%282%2C%284x%5E2%29%29\" = \"2+%2B+2%2Alog%282%2C%28abs%28x%29%29%29\".\r\n" );
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document.write( "It does not matter if you take the factor of \"2\" outside the parentheses or not.\r\n" );
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document.write( "What is REALLY IMPORTANT, is to use the sign of absolute value,  \"abs%28x%29\",  under the logarithm \r\n" );
document.write( "in the final expression.\r\n" );
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document.write( "Then (and only then) the identity \r\n" );
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document.write( "    \"log%282%2C%284x%5E2%29%29\" = \"2+%2B+2%2Alog%282%2C%28abs%28x%29%29%29\".\r\n" );
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document.write( "is valid on the entire domain, which is  {R \ {0} }, the set of all real non-zero numbers.\r\n" );
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\n" ); document.write( "\n" ); document.write( "The meaning of this assignment is to simplify the given expression accurately over the entire domain.\r
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