Hello, dorwei92!

I must assume that this is aproblem.vector

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,a right triangle.is