document.write( "Question 34700: \"SOLVING EXPONENTIAL AND LOGARITHMIC EQUATIONS\" ---> why is it that when any value of X results in a log of a negative number, it must be rejected??? \r
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document.write( "it's from a workbook that my professor created - not a textbook. \n" );
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Algebra.Com's Answer #20957 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! Consider an example log (-10) = x \n" ); document.write( "The exponential meaning of this is \n" ); document.write( "10^x=-10 \n" ); document.write( "But no power of 10 can produce a negative number. \n" ); document.write( "Oh? \n" ); document.write( "What if we make the base -10 ? \n" ); document.write( "Then (-10)^1 = -10 \n" ); document.write( "so, -10 works for this case; but what about (-10)^(1/2). \n" ); document.write( "That is imaginary. \n" ); document.write( "Negative bases just don't give the properties that log \n" ); document.write( "functions need. \n" ); document.write( "So the base must be positive and its powers can never be negative. \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " \n" ); document.write( " |