Answer:
(2a +b)·(13a^2 -5ab +b^2)
Step-by-step explanation:
The factorization of the difference of cubes is a standard form:
(p -q)^3 = (p -q)(p^2 +pq +q^2)
Here, you have ...
so the factorization is ...
(3a -(a -b))·((3a)^2 +(3a)(a -b) +(a -b)^2) . . . . substitute for p and q
= (2a +b)·(9a^2 +3a^2 -3ab +a^2 -2ab +b^2) . . . . simplify a bit
= (2a +b)·(13a^2 -5ab +b^2) . . . . . . collect terms
