An illustration showing how to construct a cycloid. "The circumference C=3.14D. Divide the rolling circle…

Illustration of 16 concentric congruent ellipses that are rotated about the center at equal intervals…

Illustration of 2 concentric congruent ellipses that are rotated about the center at 90°. The ellipses…

Illustration of 4 concentric congruent ellipses that are rotated about the center at equal intervals…

Illustration of 8 concentric congruent ellipses that are rotated about the center at equal intervals…