## Trigonometric Proof

For students of class 11-12 (age 16+)
MCP12
Posts: 1
Joined: Sat Jan 12, 2013 9:27 am

### Trigonometric Proof

Hello! This is my first post on this wonderful forum, and I hope one of many more to come.

Here is the first question to be posed:

Prove, in as elegant a manner as possible, that
$\sin x = 2^n \cdot \cos \frac {x}{2} \cdot \cos \frac{x}{x^2} \cdot \cdot \cdot \cos \frac {x}{2^n} \cdot \sin \frac{x}{2^n}$.

Posts: 217
Joined: Thu Oct 27, 2011 11:04 am
Location: mymensingh

### Re: Trigonometric Proof

Repeated use of the identity $Sin(2x)=2sin(x).cos(x)$
There can be no more elegant proof.