Question: how to find the magnitude of a vector given components?
Answer: Apply the equation. to find the magnitude, which is 1.4. Apply the equation theta = tan–1(y/x) to find the angle: tan–1(1.0/–1.0) = –45 degrees. However, note that the angle must really be between 90 degrees and 180 degrees because the first vector component is negative and the second is positive.