Question

Please help with a basic vector problem, I don't just want the answer, but a simple explanation, this is my first time doing this.

Answer 1

heard of direction cosines?

Answer 2

kind of discussed in class, but my professor is really confusing. so if you could please explain that would be great.

Answer 3

@nincompoop

Answer 4

lets look at it in 2D first.. then we ll extend it to 3D



Point P has co oridnates of (3,4)
a vector that originates from origin to this point is what we call the POSITION VECTOR (PV). Its easier to understand basics using PV. so we ll use this

this vector OP = 3i + 4j

now we can calculate the length of this vector using the right angled triangle..
so
\[|OP| = \sqrt{3^2 + 4^2}\]