document.write( "Question 1118033: If sqrt(5)= 2+ 1/a, show that a= 4+1/a \n" ); document.write( "
Algebra.Com's Answer #733260 by ikleyn(52780)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "If sqrt(5)= 2+ 1/a, show that a= 4+1/a
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document.write( "If \"sqrt%285%29\" = 2 + \"1%2Fa\",  then  \"1%2Fa\" = \"sqrt%285%29-2\"     (1)\r\n" );
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document.write( "It implies   a = \"1%2F%28sqrt%285%29-2%29\"    (2)\r\n" );
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document.write( "Rationalize the denominator in the right side of (2):\r\n" );
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document.write( "a = \"1%2F%28sqrt%285%29-2%29\" = \"1%2F%28sqrt%285%29-2%29\".\"%28sqrt%285%29%2B2%29%2F%28sqrt%285%29%2B2%29\" = \"%28sqrt%285%29%2B2%29%2F%28%28sqrt%285%29%29%5E2+-2%5E2%29\" = \"%28sqrt%285%29%2B2%29%2F%285-4%29\" = \"sqrt%285%29%2B2\".   (3)\r\n" );
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document.write( "Now in the formula  a = 4 + \"1%2Fa\"    (*)\r\n" );
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document.write( "    the left  side is  a = \"sqrt%285%29%2B2\"    (according to (3))\r\n" );
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document.write( "    the right side is  4 + \"1%2Fa\" =  (now replace \"1%2Fa\" by \"sqrt%285%29-2\", based on (1), to get )  = 4 + \"%28sqrt%285%29-2%29\" = \"sqrt%285%29%2B2\".\r\n" );
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document.write( "Thus the both sides of (*) are the same.\r\n" );
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document.write( "The statement is proved.\r\n" );
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