Show that the line AB is perpendicular CD if A,B,C,D are the points (2,3,4),(5,4,-1),(3,6,2),(1,2,0) respectively.

Find a unit vector perpendicular to the plane ABC where A,B,C are the points (3,-1,2)(1,-1,-3)(4,-3,1) respectively.

Consider the points A(2,2,-1), B(3,4,2), C(7,0,6).Find AB.

If A, B, C, D are the points (3,4,5),(4,6,3),(-1,2,4) and (1,0,5) , find the angle between C D and A B

Show that the line joining the origin to the point (2, 1, 1) is perpendicular to the line determined by the points (3, 5, -1), (4, 3, -1)

Show that the line through the points (1,-1,2), (3,4,-2) is perpendicular to the line through the points (0,3,2) and (3,5,6).

The foot of the perpendicular from the point (1, 6, 3) to the line x/(1)=(y-1)/(2)=(z-2)/(3) is

Show that the points A(1,2,7),B(2,6,3) "and" C(3,10,-1) are collinear.

Using section formula, show that the points A (2,-3,4), B(-1,2,1) and C (0, 1/3 ,2) are collinear.

Using section formula, show that the points A(2,-3,4) , B(-1,2,1) and C(0,1/3, 2) are collinear

Using vectors, show that the points A(1,2,7),B(2,6,3),C(3,10,-1) are collinear.