document.write( "Question 107071: Hi - In a recent demonstration, somebody went from this
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\n" ); document.write( "\n" ); document.write( "They're both obviously equivalent, as both result in the same answer for values of x. Can you help me to understand how this manipulation was performed, and how these two forms relate? Thanks!\r
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Algebra.Com's Answer #77878 by HyperBrain(694)\"\" \"About 
You can put this solution on YOUR website!
\"sqrt%281%2Bx%5E2%29%2Fx=sqrt%281%2B%281%2Fx%5E2%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Note that the equation above is the same as\r
\n" ); document.write( "\n" ); document.write( "\"sqrt%281%2Bx%5E2%29%2Fx=sqrt%281%2B%281%2Fx%5E2%29%29%2F%281%29\"\r
\n" ); document.write( "\n" ); document.write( "By cross multiplication,\r
\n" ); document.write( "\n" ); document.write( "\"x%28sqrt%281%2B%281%2Fx%5E2%29%29%29=1%28sqrt%281%2Bx%5E2%29%29\"
\n" ); document.write( "\"x%28sqrt%281%2B%281%2Fx%5E2%29%29%29=sqrt%281%2Bx%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "If you square both sides,\r
\n" ); document.write( "\n" ); document.write( "\"%28x%28sqrt%281%2B%281%2Fx%5E2%29%29%29%29%5E2=%28sqrt%281%2Bx%5E2%29%29%5E2\"
\n" ); document.write( "\"x%5E2%281%2B1%2Fx%5E2%29%29=%281%2Bx%5E2%29\"=\"1%2Bx%5E2\"
\n" ); document.write( "\"x%5E2%281%29+%2B+x%5E2%281%2Fx%5E2%29=1%2Bx%5E2\"
\n" ); document.write( "\"x%5E2%2B+%28x%5E2%2Fx%5E2%29=1%2Bx%5E2\"
\n" ); document.write( "\"x%5E2%2B1=1%2Bx%5E2\"-------------we're getting close! watch the next move or
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\n" ); document.write( "\n" ); document.write( "The final move....\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B1=x%5E2%2B1\"--------------can you guess what I did? From \"1%2Bx%5E2\", I
\n" ); document.write( " just interchanged \"1\" and \"x%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "Therefore, \"sqrt%281%2Bx%5E2%29%2Fx=sqrt%281%2B%281%2Fx%5E2%29%29\" is proven to be true.\r
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\n" ); document.write( "\n" ); document.write( "Power up,
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