3 ms·
How do you get a vector that's perpendicular to the line formed by p and S(-p) and in the direction of the origin?
by xtal_freq 2y ago
How do you get a vector that's perpendicular to the line formed by p and S(-p) and in the direction of the origin?
- nh23423fefe 2y agolet P = the vector p - S(-p) let Q dot P = 0 which means Q is perpendicular to P to choose between R = Q or -Q you want R dot (-p) > 0 because -p points from the line containing p and S(-p) toward the origin so you can just dot product again
- xtal_freq 2y agoHuh I’m not too far familiar with vectors. How do we know that R dot (-p) > 0 always