12.1a Lateral Area of a Cone
- Author:
- soongy
You know that the lateral area of a regular pyramid, is , where is the perimeter of the base and is the slant height. This formula can be derived by adding up the area of each lateral face. (See section 12-2, pages 482-3).
How about the lateral area of a cone? Two methods of deriving the formula () are presented here.