bantuin dong hehhehehehe

Misal
u = 3x - 2
du = 3 dx
dx = du/3

Int (3x - 2)^2 dx
= Int u^2 du/3
= Int 1/3 u^2 du
= 1/3 . 1/3 u^3 + C
= 1/9 (3x - 2)^3 + C

CARA LAIN
Int (ax + b)^n dx = 1/[a(n + 1)] . (ax + b)^(n + 1) + C

Int (3x - 2)^2 dx = 1/[3(2 + 1)] . (3x - 2)^(2 + 1) + C
= 1/9 (3x - 2)^3 + C