Hi,

What does it exactly mean when vectors are parallel? There must be something that I do not understand because in the following question:

"The lineis parallel to theLz - axis. The pointPhas a position vector (8,1,0) and lies on.L

Write down the equation ofin the forLr = a +tb."

I understand thatais the position vector andbis the direction, however no direction is directly stated. Apparently the answer for b is (0,0,1). So if the vector is parallel to the z axis why is the last number 1?

I understand that in 3D vectors, it is in the form (x,y,z).

Please explain!