简单计算一下,答案如图所示
letx=asinudx=acosu du∫√(a^2-x^2)/x^4 dx=∫ [(acosu)/(asinu)^4] .[acosu du]=(1/a^2) ∫ (cosu)^2/(sinu)^4 du=(1/a^2) ∫ (cotu)^2. (cscu)^2 du=-(1/a^2) ∫ (cotu)^2. dcotu=-[1/(3a^2)] (cotu)^3 + C=-[1/(3a^2)] [√(a^2-x^2)/x ]^3 + C