Question 50929
(X + 2p)^3 - (X - 2p)^3

=x^3+x^2(2p)+x(2p)^2+(2p)^3
-[(x^3+x^2(-2p)+x(-2p)^2+(-2p)^3]

=x^3+x^2(2p)+x(2p)^2+(2p)^3
-[(x^3-x^2(2p)+x(2p)^2-(2p)^3]

=2x^2(2p)+2(2p)^3

=4x^2+16p^3

Cheers,
Stan H.