Editing Golden angle (section)

== Derivation ==
The golden ratio is equal to ''&phi;''&nbsp;=&nbsp;''a''/''b'' given the conditions above.

Let ''&fnof;'' be the fraction of the circumference subtended by the golden angle, or equivalently, the golden angle divided by the angular measurement of the circle.

:<math> f = \frac{b}{a+b} = \frac{1}{1+\varphi}.</math>

But since

: <math>{1+\varphi} = \varphi^2,</math>

it follows that

:<math> f = \frac{1}{\varphi^2} </math>

This is equivalent to saying that ''&phi;''<sup>&nbsp;2</sup> golden angles can fit in a circle.

The fraction of a circle occupied by the golden angle is therefore

:<math>f \approx 0.381966. \,</math>

The golden angle ''g'' can therefore be numerically approximated in [[Degree (angle)|degrees]] as:

:<math>g \approx 360 \times 0.381966 \approx 137.508^\circ,\,</math>

or in radians as :

:<math> g \approx 2\pi \times 0.381966 \approx 2.39996. \,</math>