From 49eb6e7408b6573e27bae05db6e5d85990f5d93a Mon Sep 17 00:00:00 2001 From: Pritom Gogoi Date: Tue, 23 Oct 2018 14:07:28 +0530 Subject: [PATCH] update guide-text for 'surface-area-of-a-cone' (#26002) update guide-text for 'surface-area-of-a-cone' with proper-text, expressions and video-link --- .../surface-area-of-a-cone/index.md | 23 +++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/guide/english/mathematics/surface-area-of-a-cone/index.md b/guide/english/mathematics/surface-area-of-a-cone/index.md index c67b6e3670..4ccd2dd81e 100644 --- a/guide/english/mathematics/surface-area-of-a-cone/index.md +++ b/guide/english/mathematics/surface-area-of-a-cone/index.md @@ -3,13 +3,28 @@ title: Surface Area of a Cone --- ## Surface Area of a Cone -This is a stub. Help our community expand it. +A cone is a three-dimensional solid that has a circular base, which is connected by a curved surface to its vertex. The curved surface of the cone is formed by a set of line segments that connect the vertex to the circumference of the circle at the bottom. -This quick style guide will help ensure your pull request gets accepted. +The `radius of the cone 'r'` is defined by the radius of the circle formed at the bottom. The `slant height 'l'` is the distance from any point on the circle to the vertex of the cone. Lastly, `the altitude 'h'` is defined by the distance measured from the vertex to the cirle's center. - +* The `slant height 'h'` is calculated as: + + +* The `lateral surface area` is given by: + +* The `base surface area` is given by: + +Hence, the total surface area of the cone is the sum of the `lateral surface area` and the `base surface area`. + + + + #### More Information: - +* The derivation for the formula can be found at - [mathopenref.com](https://www.mathopenref.com/coneareaderivation.html) +* The link to a video explaining the derivation is given below: +Video Thumbnail Image