Orthoptic Curve

An Isoptic Curve formed from the locus of Tangents meeting at Right Angles.The orthoptic of a Parabola is its Directrix. The orthoptic of a centralConic was investigated by Monge and is a Circle concentric with the Conic Section. Theorthoptic of an Astroid is a Circle.

Lawrence, J. D. A Catalog of Special Plane Curves. New York: Dover, pp. 58 and 207, 1972.

• Functional Calculus
• Functional Derivative
• Function Field
• Function Space
• Functor
• Fundamental Class
• Fundamental Continuity Theorem
• Fundamental Discriminant
• Fundamental Forms
• Fundamental Group
• Fundamental Homology Class
• Fundamental Lemma of Calculus of Variations
• Fundamental System
• Fundamental Theorem of Algebra
• Fundamental Theorem of Arithmetic
• Fundamental Theorem of Curves
• Fundamental Theorem of Directly Similar Figures
• Fundamental Theorem of Gaussian Quadrature
• Fundamental Theorem of Genera
• Fundamental Theorem of Plane Curves
• Fundamental Theorem of Projective Geometry
• Fundamental Theorem of Space Curves
• Fundamental Theorem of Symmetric Functions
• Fundamental Theorems of Calculus
• Fundamental Unit