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Golden ratio
The golden section is a line segment sectioned into two according to the golden ratio. The total length a+b is to the longer segment a as a is to the shorter segment b.
The golden section is a line segment sectioned into two according to the golden ratio. The total length a+b is to the longer segment a as a is to the shorter segment b.
Leonardo Da Vinci's illustration from De Divina Proportione applies geometric proportions to the human face.
Leonardo Da Vinci's illustration from De Divina Proportione applies geometric proportions to the human face.
A pentagram colored to distinguish its line segments of different lengths. The four lengths are in golden ratio to one another.
A pentagram colored to distinguish its line segments of different lengths. The four lengths are in golden ratio to one another.
A Fibonacci spiral that approximates the golden spiral, using Fibonacci sequence square sizes up to 34.
A Fibonacci spiral that approximates the golden spiral, using Fibonacci sequence square sizes up to 34.
A regular square pyramid is determined by its medial right triangle, whose edges are the pyramid's apothem (a), semi-base (b), and height (h); the face inclination angle is also marked. Mathematical proportions b:h:a of and and are of particular interest in relation to Egyptian pyramids.
A regular square pyramid is determined by its medial right triangle, whose edges are the pyramid's apothem (a), semi-base (b), and height (h); the face inclination angle is also marked. Mathematical proportions b:h:a of 1:\sqrt{\varphi}:\varphi and 3:4:5\ and 1:4/\pi:1.61899\ are of particular interest in relation to Egyptian pyramids.
The sculpture Ratio by Andrew Rogers in Jerusalem is proportioned according to Fibonacci numbers; some call it Golden Ratio.
The sculpture Ratio by Andrew Rogers in Jerusalem is proportioned according to Fibonacci numbers; some call it Golden Ratio.