document.write( "Question 210295: Hi all, Im having trouble with the following Function and Domain problem. I have already asked and been given responses and answers for questions a) and b) but was hoping to get some help with the c) questions. (See below)
\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). Answer: y = (1/4)e^(x/2)
\n" ); document.write( "b) Write down the domain of f^(-1) Answer: Since the Range of y = 2*ln(4x) is f(0.01) which is -6.438 < y < 2.7726 the Domain of f^-1(x) is -6.438 < x <= 2.7726
\n" ); document.write( "c) Plot f from x = 0:01 to x = 1 and then plot f^(-1) on the same axes but only for domain values of x given by the range of f.
\n" ); document.write( "Help with c would be most appreciated.
\n" ); document.write( "-Nick.\r
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Algebra.Com's Answer #158883 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
The function f is defined by y = f(x) = 2 ln 4x, 0:01 <= x >= 1.
\n" ); document.write( "c) Plot f from x = 0:01 to x = 1 and then plot f^(-1) on the same axes but only for domain values of x given by the range of f.
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\n" ); document.write( "Find the equation of f^-1(x)
\n" ); document.write( "Start with y = 2ln(4x)
\n" ); document.write( "x = 2ln(4y)
\n" ); document.write( "ln(4y) = x/2
\n" ); document.write( "4y = e^(x/2)
\n" ); document.write( "y = (1/4)e^(x/2)
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\n" ); document.write( "Graph y = 2ln(4x) and (1/4)e^(x/2)
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\n" ); document.write( "You will have to pick the segment of f(x) where 0.01\n" ); document.write( "and the segment of f^-1(x) that has the range of f as
\n" ); document.write( "its domain.
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\n" ); document.write( "Notice that the two curves are symmetric to the line y = x.
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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