Expanding the expression:
(3a^3 - 3b) 2b - 3b (14a^3 - 4b)= 6a^3b - 6b^2 - 42a^3b + 12b^2= -36a^3b + 6b^2
Expanding the expression:
(3a^3 - 3b) 2b - 3b (14a^3 - 4b)
= 6a^3b - 6b^2 - 42a^3b + 12b^2
= -36a^3b + 6b^2