document.write( "Question 896525: How do you factor
\n" ); document.write( "x^4-84? I'm not sure how you break it up when the x is in 4th power. \n" ); document.write( "

Algebra.Com's Answer #543567 by richwmiller(17219) $\"\"$ $\"About$

You can put this solution on YOUR website!
Factor x^4-84 the same as x^2-y^2=(x-y)*(x+y)
\n" ); document.write( "It isn't as neat and pretty though
\n" ); document.write( "(x^2-2sqrt(21))*(x^2+2sqrt(21))
\n" ); document.write( "(x-sqrt(2)21^(1/4))*(x+sqrt(2)21^(1/4))*(x^2+2sqrt(21))\r
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\n" ); document.write( "\n" ); document.write( " $\"%28x%5E2-2sqrt%2821%29%29%2A%28x%5E2%2B2sqrt%2821%29%29\"$
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