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Next: Glide Reflections Up: Strip Patterns Previous: Other Translations and Mirror


Very few rotations will take the strip to itself.

Where can the center of rotation be if the rotation takes the strip to itself? If the center is not in the middle of the strip, think about a circle through that center just touching one edge of the strip but not the other. What happens under the rotation to points near that circle?
Suppose the center of rotation is on the midline y=0. What angles of rotation are possible if all points of the strip are to go to points on the strip? Think about points near a circle just touching both edges of the strip.