jawaban dari integralnya brp

[tex]misalkan \\ u = {x}^{4} - 1 \\ du = 4 {x}^{3} dx \\ dx = \frac{1}{4 {x}^{3} } du \\ subs. \\ = integral \: 4 {x}^{3} . {u}^{2} . \frac{1}{4 {x}^{3} }du \\ = integral \: {u}^{2} du \\ = \frac{1}{3} {u}^{3} \\ subs \: u = {x}^{4} - 1 \\ = \frac{1}{3} ( {x}^{4} - 1) + c[/tex]