document.write( "Question 494615: I need help factoring this: x^4-6x^2+7 \n" ); document.write( "

Algebra.Com's Answer #335725 by stanbon(75887) $\"\"$ $\"About$

You can put this solution on YOUR website!
x^4-6x^2+7
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\n" ); document.write( "Let x^2 = w
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\n" ); document.write( "w^2 - 6w + 7
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\n" ); document.write( "Use the quadratic formula to get:
\n" ); document.write( "w = [6 +- sqrt(36 - 4*7]/2
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\n" ); document.write( "w = [6 +-sqrt(8)]/2
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\n" ); document.write( "w = [3 +- sqrt(2)]
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\n" ); document.write( "solve for \"x\":
\n" ); document.write( "x^2 = 3+sqrt(2) or x^2 = 3-sqrt(2)
\n" ); document.write( "x = sqrt[3+sqrt(2)] or x = sqrt[3-sqrt(2)]
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "

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