document.write( "Question 83735: Solve the equation:\r
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document.write( "(1/6)^x = 1/216 \n" );
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Algebra.Com's Answer #60227 by bucky(2189)![]() ![]() ![]() You can put this solution on YOUR website! You can do this problem without using logarithms if you wish. The process for doing it \n" ); document.write( "involves: \n" ); document.write( ". \n" ); document.write( "First: use the power rule of exponents to raise \n" ); document.write( "exponent \"x\" is applied to both the numerator and the denominator so the given equation becomes: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "But 1 raised to the \"x\" power is always 1 no matter what the value of \"x\" is. So the equation \n" ); document.write( "simplifies to: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Notice that the numerators are equal ... both of them are 1. So for this equation to be \n" ); document.write( "true, the denominators must also be equal. Therefore you can say that: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Six squared is 36 and if you multiply that by 6 you get 216. So you can say that \n" ); document.write( "6 cubed = 216 so \"x\" must be 3 to indicate that 6 is cubed. \n" ); document.write( ". \n" ); document.write( "If you have to do the problem by using logarithms, then start with the given equation: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "and take the logarithm of both sides: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Now apply two rules of logarithms. The first rule is that in a logarithm of a quantity \n" ); document.write( "that is raised to an exponent, the exponent can be brought out to become the multiplier \n" ); document.write( "of the logarithm. Applying that rule to the left side of the equation, makes the equation \n" ); document.write( "become: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "The second rule of logarithms to apply is the one that says the log of a fraction is \n" ); document.write( "equal to the log of the numerator minus the log of the denominator. Applying that rule \n" ); document.write( "to both sides in this problem gives: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Now use the fact that log(1) = 0 and substitute 0 for log(1) on both sides to get: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "and this simplifies to: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "If you multiply both sides of this equation by -1 you get rid of the minus signs and the \n" ); document.write( "equation becomes: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Divide both sides of this equation by \n" ); document.write( "leads to: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Now use your calculator to find that for base 10 logs \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "And when you do this division on a calculator you get \n" ); document.write( ". \n" ); document.write( "Hope this helps you to understand a little more about both logarithms and also about handling \n" ); document.write( "exponents. \n" ); document.write( ". \n" ); document.write( " |