document.write( "Question 117122: Simplify\r
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Algebra.Com's Answer #85176 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"sqrt%2820%29%2F5-1%2Fsqrt%285%29\" Start with the given expression\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%2820%29%2F5-%281%2Fsqrt%285%29%29%28sqrt%285%29%2Fsqrt%285%29%29\" Multiply the second fraction by \"sqrt%285%29%2Fsqrt%285%29\". Doing this will make \r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%2820%29%2F5-sqrt%285%29%2F%28sqrt%285%29sqrt%285%29%29\" Combine the fractions\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%2820%29%2F5-sqrt%285%29%2F5\" Multiply \"sqrt%285%29sqrt%285%29\" to get \"5\". Notice how \"sqrt%285%29sqrt%285%29=%28sqrt%285%29%29%5E2=5\" shows \r
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\n" ); document.write( "\n" ); document.write( "Now that we have a rational denominator, and also a common denominator, we can combine the fractions\r
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\n" ); document.write( "\n" ); document.write( "\"%28sqrt%2820%29-sqrt%285%29%29%2F5\" Combine the numerators\r
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\n" ); document.write( "\n" ); document.write( "\"%28sqrt%284%2A5%29-sqrt%285%29%29%2F5\" Factor 20 into 4*5\r
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\n" ); document.write( "\n" ); document.write( "\"%28sqrt%284%29%2Asqrt%285%29-sqrt%285%29%29%2F5\" Break up the roots using the identity \"sqrt%28x%2Ay%29=sqrt%28x%29sqrt%28y%29\".\r
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\n" ); document.write( "\n" ); document.write( "\"%282%2Asqrt%285%29-sqrt%285%29%29%2F5\" Take the square root of the perfect square 4 to get 2\r
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\n" ); document.write( "\n" ); document.write( "Notice how we have the common term \"sqrt%285%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28%282-1%29%2Asqrt%285%29%29%2F5\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%285%29%2F5\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "So \"sqrt%2820%29%2F5-1%2Fsqrt%285%29\" simplifies to \"sqrt%285%29%2F5\". In other words, \"sqrt%2820%29%2F5-1%2Fsqrt%285%29=sqrt%285%29%2F5\". \r
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\n" ); document.write( "\n" ); document.write( "So looking at the answer you wrote, you are correct since \"%281%2F5%29sqrt%285%29\" is equivalent to \"sqrt%285%29%2F5\"\r
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\n" ); document.write( "\n" ); document.write( "If we evaluate \"sqrt%2820%29%2F5-1%2Fsqrt%285%29\" with a calculator, we get \r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%2820%29%2F5-1%2Fsqrt%285%29=0.44721359549996\"\r
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\n" ); document.write( "\n" ); document.write( "and if we evaluate \"sqrt%285%29%2F5\" with a calculator, we get \r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%285%29%2F5=0.44721359549996\"\r
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\n" ); document.write( "\n" ); document.write( "Notice how these evaluate to the same value. So this shows that \"sqrt%2820%29%2F5-1%2Fsqrt%285%29=sqrt%285%29%2F5\" and this verifies our \r
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