∫ (a²-x²)^(3/2) / x^6 dx
代x = a*sinz,dx = a*cosz dz
(a²-x²)^(3/2) = (a²-a²sin²x)^(3/2) = (a²cos²x)^(3/2) = a³cos³x
原式 = ∫ [a³cos³x / (a^6*sin^6z)] * a*cosz dz
= (1/a²)∫ csc²z * cot^4z dz
= (-1/a²)∫ cot^4z d(cotz)
= (-1/a²) * cot^5z / 5 + C
= -(a²-x²)^(5/2) / (5a²x^5) + C