Talk:Brahmagupta's formula

India Low‑importance

	India portal This article is within the scope of WikiProject India, which aims to improve Wikipedia's coverage of India-related topics. If you would like to participate, please visit the project page.IndiaWikipedia:WikiProject IndiaTemplate:WikiProject IndiaIndia articles
Low	This article has been rated as Low-importance on the project's importance scale.

Mathematics Low‑priority

	Mathematics portal This article is within the scope of WikiProject Mathematics, a collaborative effort to improve the coverage of mathematics on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.MathematicsWikipedia:WikiProject MathematicsTemplate:WikiProject Mathematicsmathematics articles
Low	This article has been rated as Low-priority on the project's priority scale.

Brahmagupta's method edit

Latest comment: 11 years ago2 comments2 people in discussion

How did Brahmagupta derive this formula? The algebra and trigonometry in the modern proof surely post-date him by a considerable amount. Rigadoun 04:58, 12 May 2006 (UTC)Reply

He didn't have the trig formula--see below. Duoduoduo (talk) 16:38, 13 June 2012 (UTC)Reply

Generalized formula is not Brahmagupta's edit

Latest comment: 11 years ago1 comment1 person in discussion

Ever since the edit of 12:22, 16 May 2004 by Rjyanco, the lede has said (with slight tweaks to the wording):

In Euclidean geometry, Brahmagupta's formula finds the area of any quadrilateral given the lengths of the sides and some of the angles. In its most common form, it yields the area of quadrilaterals that can be inscribed in a circle.

This is not right--Brahmagupta's formula is the special case formula applying only to the cyclic case. See for example the Mathworld article . I'm changing the lede to reflect this. Duoduoduo (talk) 16:38, 13 June 2012 (UTC)Reply

Add topic