lørdag den 3. februar 2018

Perpendicular tangents

Vinkelrette tangenter ( x ² )
















Two tangents to a parabola will be perpendicular (i.e. the product of
their slopes will be -1) if they are
drawn through an external point
( x₀ ; y₀ ) on the directrix ( -1 / 4 a ).

Tangents to a Parabola ( a x ² )