Hello, Unt0t!

You don't know the Distance Formula?A triangle ABC has vertices given by A(1,1,8), B(4,-3,-4) and C(-3,1,5)

(a) Determine the distance between B and C (in units).

The angle between two vectors, is given by: .(b) Find the angle formed at the vertex A (2 decimal places)

Let:

Let:

Then: .

. . . . . . . .

Therefore: .