document.write( "Question 681109: How to solve whether or not the functions are inverses of each other?\r
\n" ); document.write( "\n" ); document.write( "1)F(x)=6x-7, g(x)=(x-6)/7\r
\n" ); document.write( "\n" ); document.write( "and \r
\n" ); document.write( "\n" ); document.write( "2) f(x)=3/(x+7), g(x)=(7x+3)/x
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Algebra.Com's Answer #422570 by funmath(2933)\"\" \"About 
You can put this solution on YOUR website!
Tell whether or not the functions are inverses of each other?\r
\n" ); document.write( "\n" ); document.write( "1)F(x)=6x-7, g(x)=(x-6)/7\r
\n" ); document.write( "\n" ); document.write( "and \r
\n" ); document.write( "\n" ); document.write( "2) f(x)=3/(x+7), g(x)=(7x+3)/x\r
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If they are inverses, then their composite functions have to equal x

\n" ); document.write( "That is f(g(x))=x and g(f(x))=x.\r
\n" ); document.write( "\n" ); document.write( "1. \"f%28g%28x%29%29=f%28%28x-6%29%2F7%29\"
\n" ); document.write( "You will substitute g(x) in for the x's in f(x).
\n" ); document.write( "\"f%28g%28x%29%29=6%28%28x-6%29%2F7%29-7\"
\n" ); document.write( "\"f%28g%28x%29%29=%286x-36%29%2F7-7\"
\n" ); document.write( "Get a common denominator...
\n" ); document.write( "\"f%28g%28x%29%29=%286x-36%29%2F7-49%2F7\"
\n" ); document.write( "\"f%28g%28x%29%29=%286x-85%29%2F7\"
\n" ); document.write( "since it did not simplify to x, they are not inverses of each other.\r
\n" ); document.write( "\n" ); document.write( "
2. f(g(x))=f((7x+3)/x)

\n" ); document.write( "\"f%28g%28x%29%29=3%2F%28%287x%2B3%29%2Fx%2B7%29\"
\n" ); document.write( "Multiply the top and the bottom by x to clear the complex fraction.
\n" ); document.write( "\"f%28g%28x%29%29=3x%2F%28x%287x%2B3%29%2Fx%2B7x%29\"
\n" ); document.write( "\"f%28g%28x%29%29=3x%2F%287x%2B3%2B7x%29\"
\n" ); document.write( "\"f%28g%28x%29%29=3x%2F%2814x%2B3%29\"
\n" ); document.write( "This also doesn't simplify to x and therefore are not inverses.\r
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\n" ); document.write( "Just to clarify....this is an example where they ARE inverses.
\n" ); document.write( "3. \"f%28x%29=3%2F%28x-1%29\" and \"g%28x%29=%283%2Bx%29%2Fx\"
\n" ); document.write( "\"f%28g%28x%29%29=f%28%283%2Bx%29%2Fx%29\"
\n" ); document.write( "\"f%28g%28x%29%29=3%2F%28%28%283%2Bx%29%2Fx%29-1%29\"
\n" ); document.write( "to clear the complex fraction, multiply the top and bottom by x
\n" ); document.write( "\"f%28g%28x%29%29=3x%2F%28x%283%2Bx%29%2Fx-x%29\"
\n" ); document.write( "\"f%28g%28x%29%29=3x%2F%283%2Bx-x%29\"
\n" ); document.write( "\"f%28g%28x%29%29=3x%2F3\"
\n" ); document.write( "\"f%28g%28x%29%29=x\"
\n" ); document.write( "f(x) and g(x) ARE inverses in this case because f(g(x))=x.
\n" ); document.write( "*Note...g(f(x))=x as well....give it a try.\r
\n" ); document.write( "\n" ); document.write( "Hope that helped. Happy Calculating!!!!
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