Factorise $$(a+2b-3c)^3+(b+2c-3a)^3+(c+2a-3b)^3$$
Problem
Source: Regional Olympiad - Federation of Bosnia and Herzegovina 2011
Tags: factorization, algebra
Source: Regional Olympiad - Federation of Bosnia and Herzegovina 2011
Tags: factorization, algebra
Factorise $$(a+2b-3c)^3+(b+2c-3a)^3+(c+2a-3b)^3$$