document.write( "Question 279635: how do you get the inverse of y=2/x \n" ); document.write( "
Algebra.Com's Answer #203252 by Theo(13342)\"\" \"About 
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equation is y = 2/x\r
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\n" ); document.write( "\n" ); document.write( "solve for x.\r
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\n" ); document.write( "\n" ); document.write( "multiply both sides of the equation by x to get:\r
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\n" ); document.write( "\n" ); document.write( "xy = 2\r
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\n" ); document.write( "\n" ); document.write( "divide both sides of the equation by y to get:\r
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\n" ); document.write( "\n" ); document.write( "x = 2/y\r
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\n" ); document.write( "\n" ); document.write( "replace x with y and y with x to get:\r
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\n" ); document.write( "\n" ); document.write( "y = 2/x\r
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\n" ); document.write( "\n" ); document.write( "this equation is the inverse of itself.\r
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\n" ); document.write( "\n" ); document.write( "your equation is y = 2/x\r
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\n" ); document.write( "\n" ); document.write( "the inverse equation is y = 2/x\r
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\n" ); document.write( "\n" ); document.write( "A graph of your equation and the line y = x looks like this:\r
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\n" ); document.write( "\n" ); document.write( "\"graph+%28600%2C600%2C-10%2C10%2C-10%2C10%2C2%2Fx%2Cx%29\"\r
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\n" ); document.write( "\n" ); document.write( "based on the graph, your equation looks like it is symmetric with respect to the line y = x\r
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\n" ); document.write( "\n" ); document.write( "let's set y equal to f(x) in the original equation of y = 2/x. \r
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\n" ); document.write( "\n" ); document.write( "y = 2/x becomes f(x) = 2/x.\r
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\n" ); document.write( "\n" ); document.write( "let's set y equal to g(x) in the inverse equation of y = 2/x. \r
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\n" ); document.write( "\n" ); document.write( "y = 2/x becomes g(x) = 2/x.\r
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\n" ); document.write( "\n" ); document.write( "now we can distinguish between them.\r
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\n" ); document.write( "\n" ); document.write( "f(x) = 2/x is the original equation.
\n" ); document.write( "g(x) = 2/x is the inverse equation.\r
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\n" ); document.write( "\n" ); document.write( "the fact that they represent the same equation is an anomaly of the inverse function rules but the rules still hold.\r
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\n" ); document.write( "\n" ); document.write( "if they are truly inverse equations of each other, then for every x in f(x), we should have g(f(x)) = x.\r
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\n" ); document.write( "\n" ); document.write( "to see if that's true, let's do the following:\r
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\n" ); document.write( "\n" ); document.write( "let x = 6.\r
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\n" ); document.write( "\n" ); document.write( "f(x) = 2/x = 2/6 = 1/3\r
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\n" ); document.write( "\n" ); document.write( "since f(x) = 1/3, then g(f(x)) = g(1/3).\r
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\n" ); document.write( "\n" ); document.write( "since g(x) = 2/x, then g(1/3) = 2 / (1/3) which equals 6.\r
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\n" ); document.write( "\n" ); document.write( "we simply replace x with 1/3 in the equation.\r
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\n" ); document.write( "\n" ); document.write( "there we have it.\r
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\n" ); document.write( "\n" ); document.write( "g(f(x)) = x\r
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\n" ); document.write( "\n" ); document.write( "x = 6
\n" ); document.write( "f(x) = 1/3
\n" ); document.write( "g(1/3) = 6\r
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\n" ); document.write( "\n" ); document.write( "the test for inverse function is passed and this function is the inverse function of itself.\r
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