document.write( "Question 1087964: Find the real roots of the equation 9/x^4+8/x^2=1
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Algebra.Com's Answer #702277 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "The standard method to solve it is THIS:\r\n" );
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document.write( "1.  Introduce new variable u = .\r\n" );
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document.write( "    Then your equation takes the form\r\n" );
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document.write( "     = 0.\r\n" );
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document.write( "    Factor left side polynomial. You will get\r\n" );
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document.write( "    (9u -1)*(u+1) = 0.\r\n" );
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document.write( "    The roots are  u =   and  u = -1.\r\n" );
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document.write( "2.  Now return to the original  variable x.\r\n" );
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document.write( "    With the root  u =   you have   = ,\r\n" );
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document.write( "         which implies x = +/- 3.\r\n" );
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document.write( "    With the root  u = -1  you have   = -1,\r\n" );
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document.write( "        which HAS NO real solutions.\r\n" );
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document.write( "Answer.  The given equation has two real solutions x = 3 and x = -3.\r\n" );
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