Question

8.3
Simpleify
the following
as (3a+b)³+(3a +b)³​

Answer 1

Answer:

54a^3 + 2b^3 + 18ab^2 + 54a^2b

Step-by-step explanation:

By using the cubic formula (a+b)^3 twice a time and add it :

(3a+b)^3+(3a+b)^3

=(27a^3+b^3+9ab^2+27a*^2b)+(27a^3+b^3+9ab^2+27a^2b)

= 55^3+2b^3+18ab^2+54a^2b