document.write( "Question 1200540: f : x —> (2x + 7) / (x-2) for x ∈ R , x ≠ 2
\n" ); document.write( "a) find an expression of f^-1 (x)
\n" ); document.write( "b) State what your answer to part (a) tells you about the symmetry of the graph of y = f(x).
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Algebra.Com's Answer #834945 by Theo(13342)\"\" \"About 
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i solved for the inverse equation and it turns out that the inverse equation is the same as the regular equation.
\n" ); document.write( "here's how i did it.
\n" ); document.write( "start with y = (2x+7) / (x-2)
\n" ); document.write( "replace y with x and x with y to get:
\n" ); document.write( "x = (2y+7) / (y-2)
\n" ); document.write( "now you want to solve for y.
\n" ); document.write( "multiply both sides of the equation by (y-2) to get:
\n" ); document.write( "x * (y-2) = 2y+7
\n" ); document.write( "simplify to get:
\n" ); document.write( "yx - 2x = 2y + 7
\n" ); document.write( "add 2x to both sides of the equation and subtract 2y from both sitdes of the equation to get:
\n" ); document.write( "yx - 2y = 2x + 7
\n" ); document.write( "factor out the y on the left side of the equation to get:
\n" ); document.write( "y * (x-2) = 2x + 7
\n" ); document.write( "divide both sides of the equation by (x-2) to get:
\n" ); document.write( "y = (2x+7)/(x-2)
\n" ); document.write( "the inverse equation is the same as the regular equation *****
\n" ); document.write( "since the inverse equation is symmetric to the original equation about the line y = x, this says that the original equation is symmetric about the line y = x.
\n" ); document.write( "a graph of the original equation should show this to be true.
\n" ); document.write( "that's the only conclusion i can draw from this, since i can't think of anything else.
\n" ); document.write( "here's the graph.
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\n" ); document.write( "i found a reference that seems to talk about this.
\n" ); document.write( "it can be found at https://math.stackexchange.com/questions/541978/can-the-inverse-of-a-function-be-the-same-as-the-original-function
\n" ); document.write( "the reference calls it an involution.
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