Math Is Fun Forum

splintercell990

Member

Registered: 2006-01-23

Posts: 1

Proof - Right Triangle

Prove that triangle ABC is a right angle triangle if and only if the following condition is met:

cos(A/2) * cos(B/2) * cos(C/2) - sin(A/2) * sin(B/2) * sin(C/2) = 1/2

krisper

Member

Registered: 2005-12-20

Posts: 19

Re: Proof - Right Triangle

As I have to go to school now I will post the proof tonight.

Last edited by krisper (2006-01-24 05:30:02)

---

Humankind's inherent sense of right and wrong cannot be biologically explained.