উপ-গুণিতক কোণের সূত্রসমূহ:

1. \(\sin\theta = 2\sin\frac{\theta}{2} \cos\frac{\theta}{2}\)
2. \(\cos\theta = \cos^2\frac{\theta}{2} - \sin^2\frac{\theta}{2} = 2\cos^2\frac{\theta}{2} - 1 = 1 - 2\sin^2\frac{\theta}{2}\)
3. \(1 + \cos\theta = 2\cos^2\frac{\theta}{2}\)
4. \(1 - \cos\theta = 2\sin^2\frac{\theta}{2}\)
5. \(\sin\theta = \frac{2\tan\frac{\theta}{2}}{1 + \tan^2\frac{\theta}{2}}\)
6. \(\cos\theta = \frac{1 - \tan^2\frac{\theta}{2}}{1 + \tan^2\frac{\theta}{2}}\)
7. \(\tan\theta = \frac{2\tan\frac{\theta}{2}}{1 - \tan^2\frac{\theta}{2}}\)