I must assume that this is a vector problem.
Here's the first part . . .
Consider the lengths (magnitudes) of the three vectors:1. Points are the three vertices of a triangle in 3-space.
It is known that: .
(a) Is a right triangle? Justify your answer.
We find that: .
. . That is: .
Hence, the three sides satisfy the Pythagorean Theorem
Therefore, is a right triangle.