Expand: (3x + 2)2.
We have,
(3x + 2)2
We know that,
(a + b)3 = a3 + b3 + 3ab (a + b)
∴ (3x + 2)2 = (3x)3 + (2)3 + 3 (3x) (2) (3x + 2)
= 27x3 + 8 + 18x (3x + 2)
= 27x3 + 8 + 54x2 + 36x
= 27x3 + 54x2 + 36x + 8