I have a test on monday and I need help with these two questions, please.
1)Prove that the magnitude of the vector OP = (a,b,c) is given by |OP| = sqrt a^2+b^2+c^2
I understand how to find the magnitude, but I don't know how to prove it.
2)Give a geometrical interpretation of the vector u = (4,2,-5,2)
Do I just draw a paralellogram?