S(3×-1)8 dx tolong bantuannya

misalnya 3x - 1 = p maka diturunkan 3 dx = dp ->>> dx = 1/3 dp

maka
S (3x-1)^8 dx = S (p )^8 . 1/3 dp = 1/3 S p^8 dp = 1/3 1/9 p^9 = 1/27 (3x-1)^9

Caranya seperti ini:

Misal U  = (3x^-1)
         du = (-3x^-2) dx         didapat dari ax^n = n*a x^n-1, dimana a=3, n=(-1)

1/(-3x^-2) du = dx

∫ (3x^-1)^8 dx = ∫(u)^8 * 1/(-3x^-2) du = 1/(-3x^-2) * 1/9 u^9 + C
= 1/ (-3x^-2) * 1/9 (3x^-1) + C