Problem 3-25b - Vector difference - (B)

Determine the vector that must be added to the sum of \(A\) and \(B\) in the figure to give a net displacement of \(4.0\; km\; \text{W}\).

diagram indicating directions north and east as well as vectors A and B


That sum looks like this which could end up at the desired \(4\; km\) west.

diagram indicating C at the desired 4 km West

Which row has the correct value of the \(x\) component of the vectors?

Solution \(A_x\) \(B_x\) \(C_x\) \(R_x\)
(A) \(5.1 \sin 71\) \(6.8 \cos 52\) \(C_x\) \(4\)
(B) \(5.1 \cos 71\) \(6.8 \sin 52\) \(C_x\) \(4\)
(C) \(5.1 \cos 71\) \(6.8 \sin 52\) \(C_x\) \(-4\)
(D) \(5.1 \sin 71\) \(6.8 \cos 52\) \(C_x\) \(-4\)