∫ x^2/(a^6-x^6) dxletx^3= a^3 siny3x^2 dx= a^3.cosy dy∫ x^2/(a^6-x^6) dx= [1/(3a^3)]∫ (1/cosy) dy=[1/(3a^3)] ln|secy + tany | +C=[1/(3a^3)] ln| a^3/√(a^6-x^6) + x^3/√(a^6-x^6) | +C