document.write( "Question 309760: what is one possible value of x for which x < 2 < 1/x ? \n" ); document.write( "
Algebra.Com's Answer #221538 by Edwin McCravy(20060)\"\" \"About 
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what is one possible value of x for which x < 2 < 1/x ?
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document.write( "\"1%2F3\" is a possible value for x because\r\n" );
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document.write( "\"1%2F3+%3C++2++%3C++1%2F%281%2F3%29\"\r\n" );
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document.write( "Inverting and multiplying that last expression,\r\n" );
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document.write( "\"1%2F3+%3C++2++%3C++1%2A%283%2F1%29\"\r\n" );
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document.write( "or\r\n" );
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document.write( "\"1%2F3+%3C++2++%3C++3\"\r\n" );
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document.write( "and that is true!\r\n" );
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document.write( "Other possible values of x would be \"1%2F4\",\"1%2F5\",\"1%2F6\", etc. \r\n" );
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document.write( "How did I get that?\r\n" );
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document.write( "Greater than zero means \"positive\"\r\n" );
document.write( "Less than zero means \"negative\"\r\n" );
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document.write( "We try Case 1:  \"x+%3E+0\"  (which means x is a positive number)\r\n" );
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document.write( "\"x%3E0\"\"AND\"\"+x+%3C++2++%3C++1%2Fx\"\r\n" );
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document.write( "We multiply through the right inequality by positive number x\r\n" );
document.write( "and the inequality sign does not reverse:\r\n" );
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document.write( "\"x%3E0\"\"AND\"\"+x%5E2+%3C++2x++%3C++1\"\r\n" );
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document.write( "\"x%3E0\"\"AND\"\"x%5E2+%3C+2x+%3C+1\"\r\n" );
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document.write( "\"x%3E0\"\"AND\"\"x%5E2%3C2x\"\"AND\"\"2x%3C1\"\r\n" );
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document.write( "\"x%3E0\"\"AND\"\"x%28x-2%29%3C0\"\"AND\"\"x%3C1%2F2\"\r\n" );
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document.write( "Since x is a positive number in this case, and the product\r\n" );
document.write( "\"x%28x-2%29\" is negative, and since a positive number must \r\n" );
document.write( "be multiplied by a negative number in order to get a negative \r\n" );
document.write( "number, then \"x-2%29\" must be a negative number, so\r\n" );
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document.write( "\"x%3E0\"\"AND\"\"x-2%3C0\"\"AND\"\"x%3C1%2F2\"\r\n" );
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document.write( "\"x%3E0\"\"AND\"\"x%3C2\"\"AND\"\"x%3C1%2F2\"\r\n" );
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document.write( "In order for a positive number to be both less than 2\r\n" );
document.write( "and also less than \"1%2F2\", it needs to be less\r\n" );
document.write( "than \"1%2F2\"\r\n" );
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document.write( "So therefore:\r\n" );
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document.write( "\"0%3Cx%3C1%2F2\"\r\n" );
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document.write( "We try Case 2:  \"x+%3C+0\"  (which means x is a negative number)\r\n" );
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document.write( "\"x%3C0\"\"AND\"\"+x+%3C++2++%3C++1%2Fx\"\r\n" );
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document.write( "If we multiply the second inequality by x, which in this case is \r\n" );
document.write( "negative, we reverse the inequality symbols:\r\n" );
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document.write( "\"x%3C0\"\"AND\"\"x%5E2+%3E+2x+%3E+1\"\r\n" );
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document.write( "\"x%3C0\"\"AND\"\"x%5E2%3E2x\"\"AND\"\"2x%3C1\"\r\n" );
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document.write( "\"x%3C0\"\"AND\"\"x%5E2-2x%3C0\"\"AND\"\"x%3C1%2F2\"\r\n" );
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document.write( "\"x%3C0\"\"AND\"\"x%28x-2%29%3C0\"\"AND\"\"x%3C1%2F2\"\r\n" );
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document.write( "Since x is a negative number in this case, and the product\r\n" );
document.write( "\"x%28x-2%29\" is negative, and since a negative number must \r\n" );
document.write( "be multiplied by a positive number in order to get a negative \r\n" );
document.write( "number, then \"x-2%29\" must be a positive number. But then\r\n" );
document.write( "\"x-2%3E0\" implies \"x%3E2\" with contradicts \"x%3C0\".\r\n" );
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document.write( "So Case 2 is impossible.\r\n" );
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document.write( "We try Case 3:  x = 0\r\n" );
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document.write( "This is impossible since \"1%2Fx\" would not be defined.\r\n" );
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document.write( "Therefore only Case 1 is possible, so the solution is\r\n" );
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document.write( "\"0%3Cx%3C1%2F2\"\r\n" );
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document.write( "and the solution set is \"%22%28%22\"\"0\"\"%22%2C%22\"\"1%2F2\"\"%22%29%22\"\r\n" );
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document.write( "So x can be any positive value between 0 and \"1%2F2\", exclusive of\r\n" );
document.write( "\"1%2F2\".  x could be any fraction whose numerator is less than half \r\n" );
document.write( "its denominator.  Or x could be any decimal whose tenths digit is less \\r\n" );
document.write( "than 5, such as .437 or .33339, etc.\r\n" );
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document.write( "Edwin
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