Spiral Similarity

Please enable Java for an interactive construction (with Cinderella).

A spiral similarity results from the combination of a rotation with a scaling, i.e. an expansion or contraction.

If the center of rotation lies at the origin, this operation can as well be expressed as a matrix multiplication.

Like in the case of the rotation, this rule holds: "The columns of the matrix are the images of the unit vectors."

Download file:

Rotation $\hookleftarrow$ Contents $\hookrightarrow$ Reflections