Question 319748
x+iy = (a+ib)^3 = a^3 + 3a^2ib + 3ai^2b^2 + i^3b^3 = (a^3 - 3ab^2) + (3a^2b - b^3)i


Comparing real and imaginary components:

x = a^3 - 3ab^2; x/a = a^2 - 3b^2
y = 3a^2b - b^3; y/b = 3a^2 - b^2


x/a + y/b = 4(a^2 - b^2)