document.write( "Question 1148429: Determine whether f and g are inverse functions by evaluating f(g(x)) and g(f(x)).\r
\n" ); document.write( "\n" ); document.write( "f(x)=x^2-2, domain [0, ∞)
\n" ); document.write( "g(x)= \"+sqrt%28+x%2B+2+%29+\" , domain [-2,∞)\r
\n" ); document.write( "\n" ); document.write( "Evaluate f(g(x)).
\n" ); document.write( "f(g(x))= (Simplify your answer.)\r
\n" ); document.write( "\n" ); document.write( "Evaluate g(f(x)).
\n" ); document.write( "g(f(x))= (Simplify your answer.)\r
\n" ); document.write( "\n" ); document.write( "Are f(x) and g(x) inverse functions?
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Algebra.Com's Answer #769799 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
these look like inverses of each other because f(g(x)) = x and g(f(x)) = x.\r
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\n" ); document.write( "\n" ); document.write( "here's a reference.\r
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\n" ); document.write( "\n" ); document.write( "http://home.windstream.net/okrebs/page45.html\r
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\n" ); document.write( "\n" ); document.write( "you have f(x) = x^2-2.
\n" ); document.write( "the domain is [0,infinity)
\n" ); document.write( "the range is [-2,infinity)\r
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\n" ); document.write( "\n" ); document.write( "you have g(x) = sqrt(x+2)
\n" ); document.write( "the domain is [-2,infinity)
\n" ); document.write( "the range is [0,infinity)\r
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\n" ); document.write( "\n" ); document.write( "here's the graph of f(x) = x^2-2\r
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\n" ); document.write( "\n" ); document.write( "here's the graph of g(x) = sqrt(x+2)\r
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\n" ); document.write( "\n" ); document.write( "you solve for f(g(x)) as follows:\r
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\n" ); document.write( "\n" ); document.write( "f(x) = x^2-2
\n" ); document.write( "g(x) = sqrt(x+2)
\n" ); document.write( "to get f(g(x)), you replace the x in f(x) with g(x).
\n" ); document.write( "this means you relace the x in f(x) with sqrt(x+2).
\n" ); document.write( "f(g(x)) = (sqrt(x+2))^2-2 = x+2-2 = x\r
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\n" ); document.write( "\n" ); document.write( "g(x) = sqrt(x+2)
\n" ); document.write( "f(x) = x^2-2
\n" ); document.write( "to get g(f(x)), you replace the x in g(x) with f(x).
\n" ); document.write( "this means you replace the x in g(x) with x^2-2.
\n" ); document.write( "g(f(x)) = sqrt(x^2-2+2) = sqrt(x^2) = x\r
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\n" ); document.write( "\n" ); document.write( "since f(g(x)) = x and g(f(x)) = x, then the two functions are inverse functions to each other.\r
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