the components of a vector V can be written (Vx,Vy,Vz). what are the components and length of a vector which is te sum of the 2 vectors, V1 and V2, whose components are (8,-3.7,0) and (3.9,-8.1,-4.4)?

Answer 1

Add the corresponding components to get the components of the sum vector.

The length is the square root of the sum of the squared components

Answer 2

how do i find the angle between the summed vector and the z axis in this reference frame?

Answer 3

The cosine of that angle is vertical component divided by the vector length.

They don't ask for that angle in your original question

Answer 4

Very well