document.write( "Question 206509: please show the conjecture is false by coming up with a counterexample.
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\n" ); document.write( "the square root of a number x is always less than x.
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Algebra.Com's Answer #156048 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"sqrt%28x%29%3Cx\" Start with the given inequality.\r
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\n" ); document.write( "\n" ); document.write( "To prove this false with a counter-example, we need to use a small number (that is less than 1). I'm going to use \"1%2F4\" (since \"1%2F4%3C1\")\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%281%2F4%29%3C1%2F4\" Plug in \"x=1%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%281%29%2Fsqrt%284%29%3C1%2F4\" Break up the root.\r
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\n" ); document.write( "\n" ); document.write( "\"1%2Fsqrt%284%29%3C1%2F4\" Evaluate the square root of 1 to get 1.\r
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\n" ); document.write( "\n" ); document.write( "\"1%2F2%3C1%2F4\" Evaluate the square root of 4 to get 2.\r
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\n" ); document.write( "\n" ); document.write( "\"1%2A4%3C1%2A2\" Cross multiply (this will help us determine which side is larger)\r
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\n" ); document.write( "\n" ); document.write( "\"4%3C2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "Since the inequality is FALSE, this means that \"1%2F2%3C1%2F4\" is FALSE (it turns out that one-half is actually larger than a quarter...draw out a picture to verify yourself). So this means that \"sqrt%281%2F4%29%3C1%2F4\" is also false.\r
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\n" ); document.write( "\n" ); document.write( "So we've shown that the inequality \"sqrt%28x%29%3Cx\" is false for all real numbers.\r
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\n" ); document.write( "\n" ); document.write( "Note: it turns out that \"sqrt%28x%29%3Cx\" is only true if \"x%3E1\"
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