document.write( "Question 212746: factor completely..... 3x4-81x= \n" ); document.write( "

Algebra.Com's Answer #160678 by Earlsdon(6294) $\"\"$ $\"About$

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Factor completely:
\n" ); document.write( " $\"3x%5E4-81x\"$ First, factor out 3x from each term.
\n" ); document.write( " $\"3x%28x%5E3-27%29\"$ Notice that the binomial in the parentheses is the difference of two cubes.
\n" ); document.write( " $\"3x%28%28x%29%5E3-%283%29%5E3%29\"$
\n" ); document.write( "The difference of two cubes is factorable thus:
\n" ); document.write( " $\"A%5E3-B%5E3+=+%28A-B%29%28A%5E2%2BAB%2BB%5E2%29\"$ , so...
\n" ); document.write( " $\"3x%28%28x%29%5E3-%283%29%5E3%29+=+highlight%283x%28x-3%29%28x%5E2%2B3x%2B9%29%29\"$ \n" ); document.write( "

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