document.write( "Question 92161: Find the solution sets for the following:\r
\n" ); document.write( "\n" ); document.write( "In (3x) = 6
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Algebra.Com's Answer #67006 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given:
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\n" ); document.write( "ln (3x) = 6
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\n" ); document.write( "By the rules of logarithms, the log of a product is equal to the sum of the logs of each
\n" ); document.write( "of the terms in the product. Therefore, ln(3*x) = ln(3) + ln(x). Substitute this into the
\n" ); document.write( "given equation and it becomes:
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\n" ); document.write( "ln(3) + ln(x) = 6
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\n" ); document.write( "Subtract ln(3) from both sides to get rid of that term on the left side. After this
\n" ); document.write( "subtraction the equation is:
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\n" ); document.write( "ln(x) = 6 - ln(3)
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\n" ); document.write( "But ln(3) is just a number that you can get from a scientific calculator. Enter 3 and then
\n" ); document.write( "press the ln key. You will find that ln(3) is equal to 1.098612289. Replace ln(3) in
\n" ); document.write( "the equation with that number and you get:
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\n" ); document.write( "ln(x) = 6 - 1.098612289
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\n" ); document.write( "Perform the subtraction on the right side of the equation and the equation reduces to:
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\n" ); document.write( "ln(x) = 4.901387711
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\n" ); document.write( "Next convert this logarithmic equation into it equivalent exponential form using the following
\n" ); document.write( "rule of logarithms:
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\n" ); document.write( "\"log%28b%2Cx%29+=+y\" is equivalent to \"b%5Ey+=+x\"
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\n" ); document.write( "And in this problem the base, b, of the natural logarithms is the number e (which is
\n" ); document.write( "2.718281828).
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\n" ); document.write( "So converting to exponential form results in an equation transformation of:
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\n" ); document.write( "\"ln%28x%29+=+4.90138771\" converting to \"e%5E4.90138771+=+x\"
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\n" ); document.write( "and since e is approximately 2.718281828 this becomes:
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\n" ); document.write( "\"x+=+2.718281828%5E4.90138771\"
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\n" ); document.write( "Using a scientific calculator to raise 2.718281828 to the 4.90138771 power results in
\n" ); document.write( "an answer of:
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\n" ); document.write( "x = 134.4762643
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\n" ); document.write( "You also could have done the problem by beginning with the conversion to exponential
\n" ); document.write( "form directly. That is, starting with:
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\n" ); document.write( "ln(3x) = 6
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\n" ); document.write( "immediately raise the base e to the sixth power and set it equal to 3x as follows:
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\n" ); document.write( "\"e%5E6+=+3x\"
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\n" ); document.write( "Then divide both sides by 3 to find that:
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\n" ); document.write( "\"x+=+%28e%5E6%29%2F3\"
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\n" ); document.write( "Then you can raise e to the sixth power \"2.718281828%5E6\" and get an answer for this
\n" ); document.write( "of 403.4287935 which you then divide by 3 to find that x = 134.4762645
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\n" ); document.write( "The slight difference in the very last decimal place between this answer and the answer we
\n" ); document.write( "got using the first method involves just calculator round off in all the steps of the
\n" ); document.write( "first method. This second method is a little more accurate because the round off only occurs
\n" ); document.write( "in the very last calculation.
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\n" ); document.write( "Hope this helps you to understand the problem a little better. The basis of answering
\n" ); document.write( "this problem is knowing how to convert from logarithmic form to exponential form and you
\n" ); document.write( "need to memorize that conversion. It gets used a lot in solving logarithmic equations.
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