Describing three-dimensional structures with spherical and
... vectors. This is exactly what we want. Think about this carefully: if the input vectors are poles to planes, they are perpendicular to those planes. Therefore, a third vector that is perpendicular to both poles lies within (is contained by) both planes. The only vector to lie within both planes defi ...
... vectors. This is exactly what we want. Think about this carefully: if the input vectors are poles to planes, they are perpendicular to those planes. Therefore, a third vector that is perpendicular to both poles lies within (is contained by) both planes. The only vector to lie within both planes defi ...
A Guessing Game: Mixtilinear Incircles
... geometry problems (on the level of IMO 3/6) often amount to finding two or three critical claims; each of these claims may be no harder to prove than an IMO 1/4, but making the right guesses of what to prove can turn out to the core difficulty of the problem. For a fantastic example, see my solution ...
... geometry problems (on the level of IMO 3/6) often amount to finding two or three critical claims; each of these claims may be no harder to prove than an IMO 1/4, but making the right guesses of what to prove can turn out to the core difficulty of the problem. For a fantastic example, see my solution ...