Geometric Art: Isolines, the Valknut, Three Interlocked Triangles,
Trefoil Knot,
Parallel Lines, Geometry
for Kids, Software, iPad


Isoline
An isoline or contour line of a function of two variables
is a curve along which the function has a constant value. Isolines usually have a parallel trend.
Parallel lines are lines in a plane which do not intersect or touch each other at any point.
Valknut
The valknut is a symbol consisting of three interlocked triangles, and appears on various Germanic objects. Topologically, the interlaced form of the plain
valknut is the Borromean rings, the trefoil knot, or a closed 3link chain.
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