Simplify and also verify the result for the given values;3.(4a2-6ab+9b2) (2a + 3b); a=2,b=1

(4a^2​ - 6ab + 9b^​2) (2a + 3b)
= 2a (4a^​2 - 6ab + 9b^​2) + 3b (4a^2​ - 6ab + 9b²)
= 8a^3​ - 12a^2​b  + 18ab^​2 + 12a^​2b - 18ab^​2 + 27b^3​
=8a^3​ + 27b^​3


LHS=   a=2 ,b=1
= (4×2×2 - 6×2×1 + 9×1×1) (2×2 + 3×1)
= (16 -12 + 9) (4 + 3)
= 13 ​× 7
= 91

RHS=   8a³ + 27b³
= 8×2×2×2 + 27×1×1×1
= 64 + 27
= 91

   LHS = RHS 
    VERIFIED