document.write( "Question 1207658: Find the real solutions of the equation. \r
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document.write( "(5x^2 - 6)^(1/4) = x\r
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document.write( "I found x to be -sqrt{6} and sqrt{6}.\r
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document.write( "The textbook answer is x = sqrt{2} and x = sqrt{3}.\r
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document.write( "Help. \n" );
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Algebra.Com's Answer #845655 by Theo(13342)![]() ![]() You can put this solution on YOUR website! i solved it this way.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "start with (5x^2 - 6) ^ (1/4) = x \n" ); document.write( "raise both sides of the equation to the 4th power to get: \n" ); document.write( "5x^2 - 6 = x^4 \n" ); document.write( "subtract the left side of the equation from both sides to get: \n" ); document.write( "0 = x^4 - 5x^2 + 6 \n" ); document.write( "replace x^2 with k. \n" ); document.write( "you get k^2 - 5k + 6 = 0 \n" ); document.write( "factor to get: \n" ); document.write( "(k - 3) * (k - 2) = 0. \n" ); document.write( "solve for k to get: \n" ); document.write( "k = 3 or k = 2 \n" ); document.write( "replace k with x^2 to get: \n" ); document.write( "x^2 = 3 or x^2 = 2 \n" ); document.write( "solve for x to get: \n" ); document.write( "x = sqrt(3) or x = sqrt(2).\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |