document.write( "Question 209169: Hi all, Im having trouble with the following Function and Domain problem(s).
\n" ); document.write( "The function f is defined by y = f(x) = 2 ln 4x, 0:01 <= x >= 1 .
\n" ); document.write( "(a) Solve for x in terms of y, and hence and the formula for the inverse
\n" ); document.write( "function f^(-1)(x).
\n" ); document.write( "b) Write down the domain of f^(-1)
\n" ); document.write( "Any help would be most appreciated.
\n" ); document.write( "-Nick.
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Algebra.Com's Answer #158108 by rapaljer(4671)\"\" \"About 
You can put this solution on YOUR website!
Hi Nick!!\r
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\n" ); document.write( "\n" ); document.write( "Given \"y=+2+ln%284x%29\", you must solve for x by \"undoing\" all the operations that were done to it. You must undo mult by 2, undo the \"ln\" function, and undo multiplication by 4. That brings you down to x.\r
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\n" ); document.write( "\n" ); document.write( "Start by dividing both sides by 2:
\n" ); document.write( "\"y%2F2=+ln%284x%29\"\r
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\n" ); document.write( "\n" ); document.write( "In order to \"undo\" the \"ln\", you must raise both sides as a power of e:\r
\n" ); document.write( "\n" ); document.write( "\"e%5E%28y%2F2%29+=+e%5E%28ln%284x%29%29+\"\r
\n" ); document.write( "\n" ); document.write( "\"e%5E%28y%2F2%29+=+4x+\"\r
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\n" ); document.write( "\n" ); document.write( "Last, divide both sides by 4:\r
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\n" ); document.write( "\n" ); document.write( "\"%28e%5E%28y%2F2%29%29%2F4+=+x\"\r
\n" ); document.write( "\n" ); document.write( "In the above statements, y represents f(x).\r
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\n" ); document.write( "\n" ); document.write( "NOW, if you interchange the x and the y, the NEW y represents the inverse function \"f%5E-1%28x%29\".\r
\n" ); document.write( "\n" ); document.write( "\"y=%28e%5E%28y%2F2%29%29%2F4+=+f%5E-1%28x%29\"\r
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\n" ); document.write( "\n" ); document.write( "R^2\r
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\n" ); document.write( "\n" ); document.write( "Dr. Robert J. Rapalje, Retired
\n" ); document.write( "Seminole Community College
\n" ); document.write( "Florida\r
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