3 ms·
let 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
by nh23423fefe 2y ago
let 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