It's crazy to be able to do this problem. First, you have to understand the meaning of this passage. I probably searched, and the general idea is as follows:

There is a general in Jingbian army who is good at using guns and spears, and another general who is good at using guns is called Jue. Cai Xian shot a bunch of birds and piled them together. The pile is getting bigger. Xuan smiled and said, I hit it with one shot, and all your piles collapsed.

You know, the bird pile is a cone, and the cone has calculus. It gradually increases from an infinitesimal point and adds up to a plane cone. A certain size is a flat square when stacked together, and a flat one with a small top and a large bottom is a frustum. When a plane starts from a point and becomes a circle, it adds up to a cone.

Followed by triple integral and quadruple integral, omitted.

Excuse me, Mr. Mathematics, how to calculate this sharp cone? What is the volume of a pointed cone? When you shoot a circle, what is its volume?

I don't know how to do it. .