D 291 Antoine Verroken 1. Rayon du cercle circomscript R = 1
Coordonnées du centre O : 0 , 0
2. Coordonnées des points Ai
A1 0 , 1
A2 cos(90-360/2/n) , sin(90-360/2/n) A3 cos(90-360/n) , sin(90-36/n) An cos(90-360/2/n) , sin(90-360/2/n) A(n-1) cos(90-360/n) , sin(90-360/n) A(2n-2) cos(90-360*3/2/n) , sin(90-360*3/2/n)
3. Droite de B (a,b) et C (c,d)
( y – b ) / ( x – a ) = ( d – b ) / c – a )
4. Point d’intersection A2 - A(n-1) / A3 - An point P Point d’intersection A1 – A3 / A2 - A(2*n-2) point Q
2*n = 16
A1 0 1
A2 0.38268 0.92388
A3 0.70711 0.70711
A14 -0.92718 0.37461
A1,A3 y = -0.414207165 * x + 1
A2,A14 y = 0.41933891 * x + 0.7663468924
Qx = 0.286321537
A7 0.70711 -0.70711
A8 0.38268 -0.92388
A2,A7 y = -5.027243789 * x + 2.847709356 A3,A8 y = 5.027243789 *x - 2.847709356
Px = 0.566481
Py = 0
Px = 2*Qx
