document.write( "Question 168695: Factor....Need some help\r
\n" ); document.write( "\n" ); document.write( "x^4-13x^2+36 \n" ); document.write( "
Algebra.Com's Answer #124355 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
x^4 - 13x^2 + 36
\n" ); document.write( "Factor this like an ordinary quadratic except you have:
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\n" ); document.write( "(x^2 - 9)(x^2 - 4); (If you FOIL this you will get the original expression)
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\n" ); document.write( "Note that each factor is the \"difference of squares\" and can be further factored
\n" ); document.write( " (x^2 - 9) = (x - 3)(x + 3)
\n" ); document.write( "and
\n" ); document.write( "(x^2 - 4) = (x - 2)(x + 2)
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