document.write( "Question 710732: I cant understand this formula for the sum of differences. my example is 8y^3-1 \n" ); document.write( "

Algebra.Com's Answer #437169 by fcabanski(1391) $\"\"$ $\"About$

You can put this solution on YOUR website!
There's not much to understand. The formula is like a recipe...plug in the numbers and variables.

\n" ); document.write( " $\"a%5E3-b%5E3=%28a-b%29%2A%28a%5E2%2Bab%2Bb%5E2%29\"$

\n" ); document.write( "Recognize that the initial expression is the difference of two cubes. $\"8y%5E3=%282y%29%5E3%29\"$ so a=2y. $\"1=1%5E3\"$ so b=1.

\n" ); document.write( "The factored form is $\"%282y-1%29%2A%28%282y%29%5E2%2B%282y%2A1%29%2B1%5E2%29=%282y-1%29%2A%284y%5E2%2B2y%2B1%29\"$
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Hope the solution helped. Sometimes you need more than a solution. Contact fcabanski@hotmail.com for online, private tutoring, or personalized problem solving (quick for groups of problems.) \n" ); document.write( "

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