已知a的三分之二次方+b的三分之二次方=4,x=a+3a的三分之一次方*b的三分之二次方,

x+y=a+3a^(1/3)*b^(2/3)+b+3a^(2/3)*b^(1/3)=[a^(1/3)+b^(1/3)]^3x-y=a+3a^(1/3)*b^(2/3)-b-3a^(2/3)*b^(1/3)=[a^(1/3)-b^(1/3)]^3所以(x+y)^(2/3)+(x-y)^(2/3)=[a^(1/3)+b^(1/3)]^2+[a^(1/3)-b^(1/3)]^2=2[a^(2/3)+...