No 27 ya kawan, terima kasih

∫ x^2 √(2x^3 - 1) dx

Misal
u = 2x^3 - 1
du = 6x^2 dx => dx = du/(6x^2)

∫ x^2 √u du/(6x^2)
= ∫ 1/6 u^(1/2) di
= (1/6)/(3/2) u^(3/2) + C
= 1/9 (2x^3 - 1)^(3/2) + C