document.write( "Question 1039561: Use the properties of exponents to prove the Power Property of Logarithms. \n" ); document.write( "
Algebra.Com's Answer #654384 by Edwin McCravy(20065)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "The power property of logarithms, which we \r\n" );
document.write( "are to prove, is\r\n" );
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document.write( "(1)   \"log%28B%2C%28A%5EC%29%29\"\"%22%22=%22%22\"\"C%2Alog%28B%2C%28A%29%29\"\r\n" );
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document.write( "But first we prove this: \r\n" );
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document.write( "(2)   \"A+\"\"%22%22=%22%22\"\"+B%5Elog%28B%2CA%29\"  \r\n" );
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document.write( "Let \"log%28B%2CA%29\"\"%22%22=%22%22\"\"x\"\r\n" );
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document.write( "Then by definition of logarithm\r\n" );
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document.write( "\"A+\"\"%22%22=%22%22\"\"+B%5Ex\"\r\n" );
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document.write( "Substitute for x\r\n" );
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document.write( "\"A+\"\"%22%22=%22%22\"\"+B%5Elog%28B%2CA%29\"\r\n" );
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document.write( "So we have proved (2).\r\n" );
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document.write( "Let \"log%28B%2CA%5EC%29\"\"%22%22=%22%22\"\"y\"\r\n" );
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document.write( "Then by the definition of logarithm:\r\n" );
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document.write( "\"B%5Ey\"\"%22%22=%22%22\"\"A%5EC\"\r\n" );
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document.write( "Using (2) to replace A\r\n" );
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document.write( "\"B%5Ey\"\"%22%22=%22%22\"\"%28B%5Elog%28B%2CA%29%29%5EC\"\r\n" );
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document.write( "Use the rule of multiplying \r\n" );
document.write( "exponents on the right:\r\n" );
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document.write( "\"B%5Ey\"\"%22%22=%22%22\"\"B%5E%28C%2Alog%28B%2CA%29%29\"\r\n" );
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document.write( "Equate the powers of B\r\n" );
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document.write( "\"y\"\"%22%22=%22%22\"\"C%2Alog%28B%2CA%29\"\r\n" );
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document.write( "Since \"y\"\"%22%22=%22%22\"\"log%28B%2CA%5EC%29\"\r\n" );
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document.write( "\"log%28B%2CA%5EC%29\"\"%22%22=%22%22\"\"C%2Alog%28B%2CA%29\"\r\n" );
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document.write( "So we have proved (1)\r\n" );
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document.write( "Edwin
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