document.write( "Question 1026531: 4/x-3 + 2x\xsquared-9 = 1/x+3 \n" ); document.write( "
Algebra.Com's Answer #853899 by ikleyn(53742)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "4/(x-3) + (2x)/(x^2-9) = 1/(x+3)
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\n" ); document.write( "\n" ); document.write( "        This problem is very tricky.\r
\n" ); document.write( "\n" ); document.write( "        It contains a hidden trap that's easy to fall into.\r
\n" ); document.write( "\n" ); document.write( "        Tutor @mananth didn't avoid this trap — he fell into it and produced an incorrect solution, \r
\n" ); document.write( "\n" ); document.write( "        for which he deserves a solid F.\r
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\n" ); document.write( "\n" ); document.write( "        Below is my correct solution to replace @mananth's incorrect one.\r
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document.write( "Your starting equation is \r\n" );
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document.write( "    \"4%2F%28x-3%29\" + \"%282x%29%2F%28x%5E2-9%29\" = \"1%2F%28x%2B3%29\".\r\n" );
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document.write( "Notice that the domain of this equation is the set of all real numbers except of x = 3 and/or x = -3,\r\n" );
document.write( "where the denominators are not defined.\r\n" );
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document.write( "So, we will work on the domain x =/= -3  and  x =/= 3.\r\n" );
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document.write( "Multiply both sides by  (x^2-3).  You will get \r\n" );
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document.write( "    4(x+3) + 2x = x - 3,\r\n" );
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document.write( "    4x + 12 + 2x = x - 3,\r\n" );
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document.write( "    6x - x = -3 - 12\r\n" );
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document.write( "       5x  =    -15,\r\n" );
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document.write( "        x  =    -15/5 = -3.\r\n" );
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document.write( "But x = -3 is not in the domain.\r\n" );
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document.write( "So, we conclude that the given equation HAS NO solutions in its domain.    <<<---===  ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved correctly.\r
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