document.write( "Question 70663: The demand function for a certain commodity is given by p=80e exponent fraction -q/2 Write q as a function of p \n" ); document.write( "
Algebra.Com's Answer #50448 by bucky(2189)\"\" \"About 
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\"p+=+80e%5E%28-q%2F2%29\" Solve for q.
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\n" ); document.write( "This is what I understand your problem to be. Assuming this is correct, you can take the ln
\n" ); document.write( "(natural logarithm which has the base e) of both sides and the problem becomes:
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\n" ); document.write( "\"+ln%28p%29=+ln%2880%2Ae%5E%28-q%2F2%29%29\"
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\n" ); document.write( "But the logarithm of a product is equals the sum of the logarithms of the two terms being
\n" ); document.write( "multiplied. Therefore, we can split the right side into the sum of two logarithms as follows:
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\n" ); document.write( "\"+ln%28p%29=+ln%2880%29%2B+ln%28e%5E%28-q%2F2%29%29\"
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\n" ); document.write( "Subtract ln(80) from both sides to get:
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\n" ); document.write( "\"+ln%28p%29+-+ln%2880%29+=++%2B+ln%28e%5E%28-q%2F2%29%29\"
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\n" ); document.write( "By the rules of logarithms, the difference of the logarithms of two quantities can be
\n" ); document.write( "re-written as the logarithm of the quotients of the quantities. This translates to:
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\n" ); document.write( "\"+ln%28p%29+-+ln%2880%29+=+ln%28p%2F80%29\"
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\n" ); document.write( "Substituting this as a replacement for the left side results in:
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\n" ); document.write( "\"+ln%28p%2F80%29+=+ln%28e%5E%28-q%2F2%29%29\"
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\n" ); document.write( "Then by a rule of exponents in logarithms, the exponent of a term in a logarithm becomes the
\n" ); document.write( "multiplier of the logarithm of the term on the right side. In this case \"%28-q%2F2%29\"
\n" ); document.write( "becomes the multiplier of ln(e) and the right side of the equation is changed as shown below:
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\n" ); document.write( "\"+ln%28p%2F80%29+=+%28-q%2F2%29%2Aln%28e%29\"
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\n" ); document.write( "But ln(e) = 1, and when this substitution is made the equation becomes:
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\n" ); document.write( "\"+ln%28p%2F80%29+=+%28-q%2F2%29\"
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\n" ); document.write( "Multiply both sides of the equation by -2 and the equation becomes:
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\n" ); document.write( "\"+-2%2Aln%28p%2F80%29+=+q\"
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\n" ); document.write( "This is the answer, but there is one additional constraint. The value of p must be greater
\n" ); document.write( "than zero or else you would be taking the ln of a negative number or zero and those are
\n" ); document.write( "outside of the allowed values of numbers that the ln function can operate on.
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\n" ); document.write( "Hopes this gives you some additional insight about the subject of logarithms and natural
\n" ); document.write( "logarithms in particular.
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