document.write( "Question 1104382: if m - 1/m = 5; find:\r
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Algebra.Com's Answer #719167 by ikleyn(52781)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "\"m+-+1%2Fm\" = 5  ====>\r\n" );
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document.write( "m^2 - 5m - 1 = 0  ====>  (apply the quadratic formula)\r\n" );
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document.write( "\"m%5B1%2C2%5D\" = \"%285+%2B-+sqrt%285%5E2+-+4%2A%28-1%29%29%29%2F2\" = \"%285+%2B-+sqrt%2829%29%29%2F2\".\r\n" );
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document.write( "In other words,   \"m%5B1%5D\" = \"%285+%2B+sqrt%2829%29%29%2F2\",  \"m%5B2%5D\" = \"%285+-+sqrt%2829%29%29%2F2\".\r\n" );
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document.write( "Notice that   \"m%5B1%5D%2Am%5B2%5D\" = -1.\r\n" );
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document.write( "You can check it by making direct calculations\r\n" );
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document.write( "   \"m%5B1%5D%2Am%5B2%5D\" = \"%28%285+%2B+sqrt%2829%29%29%2F2%29%2A%28%285+-+sqrt%2829%29%29%2F2%29\" = \"%2825-29%29%2F%282%2A2%29\" = \"%28-4%29%2F4\" = -1,\r\n" );
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document.write( "or derive it from the Vieta's theorem.\r\n" );
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document.write( "Thus  \"m%5B1%5D%5E%28-1%29\" = \"1%2Fm%5B1%5D\" = \"-m%5B2%5D\"   and  \"m%5B2%5D%5E%28-1%29\" = \"1%2Fm%5B2%5D\" = \"-m%5B1%5D\".\r\n" );
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document.write( "It implies   \"m%5B1%5D%5E%28-2%29\" = \"m%5B2%5D%5E2\" = \"%28%285+-+sqrt%2829%29%29%2F2%29%5E2\" = \"%2825-10%2Asqrt%2829%29+%2B+29%29%2F4\" = \"%2854-10%2Asqrt%2829%29%29%2F4\" = \"%2827-5%2Asqrt%2829%29%29%2F2\",   and\r\n" );
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document.write( "             \"m%5B2%5D%5E%28-2%29\" = \"m%5B1%5D%5E2\" = \"%28%285+%2B+sqrt%2829%29%29%2F2%29%5E2\" = \"%2825%2B10%2Asqrt%2829%29+%2B+29%29%2F4\" = \"%2854%2B10%2Asqrt%2829%29%29%2F4\" = \"%2827%2B5%2Asqrt%2829%29%29%2F2\".\r\n" );
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document.write( "Thus you have\r\n" );
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document.write( "            \"m%5B1%5D%5E2\" = \"%2827%2B5%2Asqrt%2829%29%29%2F2\",  \"1%2Fm%5B1%5D%5E2\" = \"%2827-5%2Asqrt%2829%29%29%2F2\",  which implies  \"m%5B1%5D%5E2\" - \"1%2Fm%5B1%5D%5E2\" = \"5%2Asqrt%2829%29\",   and\r\n" );
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document.write( "            \"m%5B2%5D%5E2\" = \"%2827-5%2Asqrt%2829%29%29%2F2\",  \"1%2Fm%5B2%5D%5E2\" = \"%2827%2B5%2Asqrt%2829%29%29%2F2\",  which implies  \"m%5B2%5D%5E2\" - \"1%2Fm%5B2%5D%5E2\" = \"-5%2Asqrt%2829%29\",\r\n" );
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\n" ); document.write( "\n" ); document.write( "Answer.   If  \"m\" - \"1%2Fm\" = 5,  then this equation has  TWO solutions;  correspondingly,  \"m\"  has  TWO values; \r
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\n" ); document.write( "\n" ); document.write( "                correspondingly,  \"m%5E2\"  has  TWO values,   and,  correspondingly,  \"m%5E2\" - \"1%2Fm%5E2\"  has two values   +/- \"5%2Asqrt%2829%29\".\r
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