document.write( "Question 1149771: How do I solve 3x(to the 4th power)-2x(to the 2nd power)=16 \n" ); document.write( "
Algebra.Com's Answer #771103 by ikleyn(52777)\"\" \"About 
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document.write( "    3x^4 - 2x^2 = 16.\r\n" );
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document.write( "Introduce new variable t = x^2.\r\n" );
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document.write( "Then your equation takes the form\r\n" );
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document.write( "    3t^2 - 2t - 16 = 0.\r\n" );
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document.write( "Solve it using the quadratic formula\r\n" );
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document.write( "    \"t%5B1%2C2%5D\" = \"%282+%2B-+sqrt%282%5E2+%2B+4%2A3%2A16%29%29%2F%282%2A3%29\" = \"%282+%2B-+sqrt%28196%29%29%2F6\" = \"%282+%2B-+14%29%2F6\".\r\n" );
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document.write( "Only positive root is acceptable (since  t = x^2),  t = \"%282+%2B+14%29%2F6\" = \"16%2F6\" = \"8%2F3\".\r\n" );
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document.write( "It implies  x^2 = \"8%2F3\";  hence,  x = +/- \"sqrt%288%2F3%29\" = +/- \"%282%2Asqrt%286%29%29%2F3\".    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Introducing new variable is the STANDARD WAY solving such problems.\r
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