|
| |||
compares the -coordinates of and the horizontal projection of p on h; see (a) in the figure below. | ||||
|
| |||
compares the -coordinates of the horizontal projection of p on h1 and on h2; see (b) in the figure below. | ||||
|
| |||
Let be the intersection of lines and . This function compares the -coordinates of and the horizontal projection of p on h; see (c) in the figure below. | ||||
|
| |||
Let be the intersection of lines and . This function compares the -coordinates of the horizontal projection of p on h1 and on h2; see (d) in the figure below. |