y=±[a^（2/3）-x^(2/3)]^(3/2),星形线分成上下两个半支,考虑X轴对称关系,只求上半支即可,从-a至a以Y轴左右对称,可求从0至a积分,再乘以2,V=2π∫[0,a]{[a^(2/3)-x^(2/3)]^(3/2)}^2dx=2π∫[0,a][a^2-3a^(4/3)x^(2/3)...