Hi Leonardo, I am glad you found this helpful, but what you want is not the intersection of those spheres….
Let us consider a 2D scenario. Here we have 3 circles with their intersection in blue:
But, if I understand it correctly, you want the green+blue area.
Which means, you’d have to take the intersection of any combination of two circles and then ‘add’ them together (in Boolean terms, this is called Union).
See if you can do this and show the result or ask if you get stuck 🙂