The perimeter of isosceles triangle is 2p, it revolves around the bottom to form a geometry. When we ask the length of each side of the triangle, the volume of the geometry is the largest?

The perimeter of isosceles triangle is 2p, it revolves around the bottom to form a geometry. When we ask the length of each side of the triangle, the volume of the geometry is the largest?

If the waist length is x, the length of the bottom edge is 2p-2x; after rotation, there are two cones. The height of a single cone h is equal to half of the bottom edge = P-X; and the radius of the bottom circle r of the cone is equal to the height of the bottom edge of the triangle, which is equal to (x ^ 2 - (P-X) ^ 2) under the root sign