Posts tagged 'rotations'

W.02 Lineations, Central Rotations & Reflections in Lines

For any non-null line l = <a : b : c> over a field F (char F != 2), the reflection sigma_l maps every point A = [x, y] and every line m = <a_2 : b_2 : c_2> to exact rational images whose denominators depend only on the quadratic norm a^2 + b^2, without radicals or angles.