English Dictionary

When you fix a point P and a plane curve C, the pedal curve shows the locus of points X such that PX is perpendicular to the tangent at X, often revealing unexpected symmetries.

平面曲線Cと固定点Pを定めると、Pから曲線Cの接線に下ろした垂線の足の軌跡、すなわち点XでPXが接線に垂直になるような点の軌跡（ペダル曲線）はしばしば意外な対称性を示す。