document.write( "Question 244874: x^4-81 \n" ); document.write( "
Algebra.Com's Answer #179025 by nerdybill(7384)\"\" \"About 
You can put this solution on YOUR website!
If you had a \"difference of squares\":
\n" ); document.write( "a^2 - b^2
\n" ); document.write( "you can factor as:
\n" ); document.write( "(a+b)(a-b)
\n" ); document.write( ".
\n" ); document.write( "For your problem:
\n" ); document.write( "x^4-81
\n" ); document.write( "we can rewrite as a \"difference of squares\":
\n" ); document.write( "(x^2)^2 - 9^2
\n" ); document.write( "Thus we can factor as:
\n" ); document.write( "(x^2+9)(x^2-9)
\n" ); document.write( "But wait, the right term is also a \"difference of squares\":
\n" ); document.write( "(x^2+9)(x^2-3^2)
\n" ); document.write( "(x^2+9)(x+3)(x-3) -- final answer\r
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