Golden Gnomon


The golden gnomon is the obtuse isosceles triangle whose ratio of side to base lengths is given by 1/phi=phi-1, where phi is the golden ratio. Such a triangle has angles of 36 degrees-36 degrees-108 degrees and can be constructed from a regular pentagon as illustrated above in red. The corresponding 36-72-72 triangle with side-to-base ratio phi is a golden triangle.

Golden triangles and gnomons can be dissected into smaller triangles that are golden gnomons and golden triangles (Livio 2003, p. 79).

See also

Golden Angle, Golden Ratio, Golden Rectangle, Golden Triangle, Isosceles Triangle

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Livio, M. The Golden Ratio: The Story of Phi, the World's Most Astonishing Number. New York: Broadway Books, p. 79, 2002.

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Golden Gnomon

Cite this as:

Weisstein, Eric W. "Golden Gnomon." From MathWorld--A Wolfram Web Resource.

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