If p + q = 6 and pq = 4, then what is the value of 3(p^3 + q^3)?

If p + q = 6

pq = 4

$3(p^3 + q^3)$ = ?

If a + b  = n

then, $a^3 + b^3$ = n³ - 3 × nab

$3(p^3 + q^3)$ =  3 × (6³ - 3 × 6 × 4) = 3 × 144 = 432