67. ORYX ANGLE

The wonderful oryx antelope in Africa has almost straight swept back horns. Can you estimate the angle they make in this photo? Would this be the actual angle?

Angle is the basic building block in trigonometry, although the name ‘trigonometry’ comes from triangle – three angles. There are a number of simple ratios that can be associated with an angle : sine, cosine, tangent, cosecant, secant and cotangent, and there are various nice relationships between them.
For example: sin ² + cos ² = 1.

Trigonometry is very important in surveying and navigation, although these days with the use of GPS and modern surveying aids, its use has become more theoretical than practical

http://en.wikipedia.org/wiki/Trigonometry

http://en.wikipedia.org/wiki/Angle