document.write( "Question 1208097: If x + 1/x = √3
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Algebra.Com's Answer #846253 by ikleyn(52781)\"\" \"About 
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document.write( "If  x + 1/x = \"sqrt%283%29\", then\r\n" );
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document.write( "    \"x%5E2\" + 1 = \"sqrt%283%29%2Ax\"\r\n" );
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document.write( "    \"x%5E2\" - \"sqrt%283%29%2Ax\" + 1 = 0.\r\n" );
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document.write( "It is the general form of a quadratic equation  ax^2 + bx + c = 0\r\n" );
document.write( "with a= 1, b= \"-sqrt%283%29\", c= 1.\r\n" );
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document.write( "Apply the quadratic formula to find the roots\r\n" );
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document.write( "    \"x%5B1%2C2%5D\" = \"%28-b+%2B-+sqrt%28b%5E2-4ac%29%29%2F%282a%29\" = \"%28sqrt%283%29+%2B-+sqrt%28%28sqrt%283%29%29%5E2-4%2A1%2A1%29%29%2F%282%2A1%29\" = \"%28sqrt%283%29+%2B-+sqrt%283-4%29%29%2F2\" = \"%28sqrt%283%29+%2B-+sqrt%28-1%29%29%2F2\" = \"%28sqrt%283%29+%2B-+i%29%2F2\".\r\n" );
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document.write( "So,  \"x%5B1%5D\" = \"%28sqrt%283%29%2Bi%29%2F2\" = \"cis%28pi%2F6%29\";\r\n" );
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document.write( "     \"x%5B2%5D\" = \"%28sqrt%283%29-i%29%2F2\" = \"cis%28-pi%2F6%29\".\r\n" );
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document.write( "Thus  \"x%5B1%5D\"  is a complex number with the modulus of 1 and the argument of  \"pi%2F6\".\r\n" );
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document.write( "      \"x%5B2%5D\"  is a complex number with the modulus of 1 and the argument of  \"-pi%2F6\".\r\n" );
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document.write( "For  x = \"x%5B1%5D\" = \"cis%28pi%2F6%29\",  we have  \r\n" );
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document.write( "     \"x%5E18\" + \"x%5E12\" + 1 = \"cis%2818%2A%28pi%2F6%29%29\" + \"cis%2812%2A%28pi%2F6%29%29\" + 1 = \"cis%283pi%29\" + \"cis%282pi%29\" + 1 = -1 + 1 + 1 = 1.\r\n" );
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document.write( "For  x = \"x%5B2%5D\" = \"cis%28-pi%2F6%29\",  we have  \r\n" );
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document.write( "     \"x%5E18\" + \"x%5E12\" + 1 = \"cis%2818%2A%28-pi%2F6%29%29\" + \"cis%2812%2A%28-pi%2F6%29%29\" + 1 = \"cis%28-3pi%29\" + \"cis%28-2pi%29\" + 1 = -1 + 1 + 1 = 1.\r\n" );
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document.write( "So, for both values of roots, we have  \"x%5E18\" + \"x%5E12\" + 1 = 1.\r\n" );
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document.write( "At this point, the solution is complete.\r\n" );
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document.write( "ANSWER.  If  x + 1/x = \"sqrt%283%29\",  then  \"x%5E18\" + \"x%5E12\" + 1 = 1.\r\n" );
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