因为d(x^3)=3x^2dx 所以dx=d(x^3)/3(x^2) 原式=∫1/[(x^6+4)*x*3x^2] dx =∫1/[(x^6+4)*3x^3] d(x^3) 令x^3=t 原式=(1/3)∫1/[(t^2+4)t] d(t) =(1/3)∫1/[(t^2+4)t*2t] d(t^2) =(1/6)∫1/[(t^2+4)t^2] d(t^2) =(1/24...