document.write( "Question 1050453: 35x^4+2x^2-1=0
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Algebra.Com's Answer #666000 by ikleyn(52778) $\"\"$ $\"About$

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document.write( "This equation is called biquadratic (the degrees of the unknown \"x\" are 4, 2 and zero).\r\n" );
document.write( "The method of solving such equations is as follows:\r\n" );
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document.write( "Introduce new variable y = x^2.  Then your equation takes the form\r\n" );
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document.write( "35y^2 + 2y - 1 = 0.\r\n" );
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document.write( "It is just a quadratic equation, and you can apply the quadratic formula to solve it:\r\n" );
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document.write( " =  =  = .\r\n" );
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document.write( " =  = .   =  = .\r\n" );
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document.write( "Since y = x^2, we are interested in positive \"y\" only.\r\n" );
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document.write( "Thus we have x^2 =  and, hence, x = +/- = +/-.\r\n" );
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document.write( "Answer. The two real roots of the original equation are +/-.\r\n" );
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\n" ); document.write( "\n" ); document.write( "See the lesson \r
\n" ); document.write( "\n" ); document.write( " - Solving polynomial equations of high degree by introducing a new variable\r
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