document.write( "Question 74104: can you help me to explain this equation?\r
\n" ); document.write( "\n" ); document.write( "If f(x)=x-1/x+1 then f(x)+f(1/x)=\r
\n" ); document.write( "\n" ); document.write( "this is a homework assignment..but not in our book..thanks
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Algebra.Com's Answer #53095 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"f%28x%29=%28x-1%29%2F%28x%2B1%29\"If thats what f(x) looks like then we're going to add that to f(1/x).
\n" ); document.write( "To find f(1/x) we simply plug in (1/x) in for every x in the original equation.
\n" ); document.write( "\"f%281%2Fx%29=%28highlight%281%2Fx%29-1%29%2F%28highlight%281%2Fx%29%2B1%29\"
\n" ); document.write( "\"f%281%2Fx%29=%28%281%2Fx%29-%28x%2Fx%29%29%2F%28%281%2Fx%29%2B%28x%2Fx%29%29\"
\n" ); document.write( "\"f%281%2Fx%29=%28%281-x%29%2Fx%29%2F%28%281%2Bx%29%2Fx%29\"
\n" ); document.write( "\"f%281%2Fx%29=%28%281-x%29%2Fcross%28x%29%29%2A%28cross%28x%29%2F%281%2Bx%29%29\"
\n" ); document.write( "So f(1/x) equals
\n" ); document.write( "\"f%281%2Fx%29=%28%281-x%29%2F%281%2Bx%29%29\"
\n" ); document.write( "Add this to f(x)
\n" ); document.write( "\"f%28x%29%2Bf%281%2Fx%29=%28x-1%29%2F%28x%2B1%29%2B%28%281-x%29%2F%281%2Bx%29%29\"
\n" ); document.write( "\"f%28x%29%2Bf%281%2Fx%29=%28x-x%2B1-1%29%2F%28x%2B1%29\"
\n" ); document.write( "\"f%28x%29%2Bf%281%2Fx%29=%280%29%2F%28x%2B1%29\"
\n" ); document.write( "\"f%28x%29%2Bf%281%2Fx%29=0\"
\n" ); document.write( "So for any x
\n" ); document.write( "\"f%28x%29%2Bf%281%2Fx%29=0\"
\n" ); document.write( "


\n" ); document.write( "Check:
\n" ); document.write( "We can let x equal any number. Lets make x=2
\n" ); document.write( "\"f%28x%29=%28x-1%29%2F%28x%2B1%29\"Plug in x=2
\n" ); document.write( "\"f%282%29=%282-1%29%2F%282%2B1%29=1%2F3\"
\n" ); document.write( "\"f%281%2Fx%29=%28%281-x%29%2F%281%2Bx%29%29\"Plug in x=2
\n" ); document.write( "\"f%281%2F2%29=%281-2%29%2F%281%2B2%29\"
\n" ); document.write( "\"f%281%2F2%29=-1%2F3\"
\n" ); document.write( "\"f%28x%29%2Bf%281%2Fx%29=f%282%29%2Bf%281%2F2%29=1%2F3-1%2F3=0\"Add the two equations. This shows that our answer works. \n" ); document.write( "

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