6.
A = [1, 0], B = [4, 2], P = [3·t, 2 + t]
AB = [3, 2]
AP = [3·t - 1, t + 2]
BP = [3·t - 4, t]
Rechter Winkel bei A
[3, 2]·[3·t - 1, t + 2] = 11·t + 1 = 0 --> t = -1/11 --> P = [- 3/11, 21/11]
Rechter Winkel bei B
[3, 2]·[3·t - 4, t] = 11·t - 12 = 0 --> t = 12/11 --> P = [36/11, 34/11]
Rechter Winkel bei P
[3·t - 1, t + 2]·[3·t - 4, t] = 10·t^2 - 13·t + 4 = 0 --> t1 = 4/5 ∨ t2 = 1/2 --> P1 = [12/5, 14/5] ∨ P2 = [3/2, 5/2]