Question 1017814
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The general formula is 


{{{a^3 - b^3}}} = {{{(a-b)*(a^2 + ab + b^2)}}}.


See the lesson <A HREF=http://www.algebra.com/algebra/homework/Polynomials-and-rational-expressions/The-difference-of-cubes-formula.lesson>The difference of cubes formula</A> in this site.


It is like 2 x 2 = 4. Of the same fundamental level.