document.write( "Question 83735: Solve the equation:\r
\n" ); document.write( "\n" ); document.write( "(1/6)^x = 1/216
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Algebra.Com's Answer #60227 by bucky(2189)\"\" \"About 
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You can do this problem without using logarithms if you wish. The process for doing it
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\n" ); document.write( "First: use the power rule of exponents to raise \"1%2F6\" to the x power. By this rule the
\n" ); document.write( "exponent \"x\" is applied to both the numerator and the denominator so the given equation becomes:
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\n" ); document.write( "\"1%5Ex%2F6%5Ex+=+1%2F216\"
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\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:
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\n" ); document.write( "\"1%2F6%5Ex+=+1%2F216\"
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\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:
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\n" ); document.write( "\"6%5Ex+=+216\"
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\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.
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\n" ); document.write( "If you have to do the problem by using logarithms, then start with the given equation:
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\n" ); document.write( "\"%281%2F6%29%5Ex+=+1%2F216\"
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\n" ); document.write( "and take the logarithm of both sides:
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\n" ); document.write( "\"log%28%281%2F6%29%5Ex%29+=+log%281%2F216%29\"
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\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:
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\n" ); document.write( "\"x%2A%28log%281%2F6%29%29+=+log%281%2F216%29\"
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\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:
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\n" ); document.write( "\"x%2A%28log%281%29-log%286%29%29+=+log%281%29-+log+%28216%29\"
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\n" ); document.write( "Now use the fact that log(1) = 0 and substitute 0 for log(1) on both sides to get:
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\n" ); document.write( "\"x%2A%280-log%286%29%29+=+0+-+log+216\"
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\n" ); document.write( "and this simplifies to:
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\n" ); document.write( "\"x%2A%28-log%286%29%29+=+-log%28216%29\"
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\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:
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\n" ); document.write( "\"x%2Alog%286%29+=+log%28216%29\"
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\n" ); document.write( "Divide both sides of this equation by \"log%286%29\" to solve for x. This division
\n" ); document.write( "leads to:
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\n" ); document.write( "\"x+=+log%28216%29%2Flog%286%29\"
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\n" ); document.write( "Now use your calculator to find that for base 10 logs \"log%28216%29+=+2.334453751\" and
\n" ); document.write( "\"log%286%29+=+0.77815125\". Substitute these two values to get:
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\n" ); document.write( "\"x+=+2.334453751%2F0.77815121\"
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\n" ); document.write( "And when you do this division on a calculator you get \"x+=+3\".
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\n" ); document.write( "Hope this helps you to understand a little more about both logarithms and also about handling
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