Posted by Jessica on Thursday, February 24, 2011 at 2:16am.
The scalar triple product P among three vectors U,V and W is defined as follows:
P=U.(VxW)
|P| represents the volume of the parallelepiped formed by the vectors U, V and W.
Consequently, if U, V and W are coplanar, P=0.
Since 4 points (A,B,C,D) are given, three vectors can be formed where
U=AB, V=AC, and W=AD.
Calculate the triple scalar product as described above and if the result is zero, then the four points are coplanar.
yes