Chapter 3, Problem 2Q

The two vectors shown in Fig. 3-21 lie in an xy plane. What are the signs of the x and y components, respectively, of (a) ${\stackrel{\to }{d}}_{\text{1}}\text{+}{\stackrel{\to }{d}}_{\text{2}}$, (b) ${\stackrel{\to }{d}}_{\text{1}}-{\stackrel{\to }{d}}_{\text{2}}$, and (c) ${\stackrel{\to }{d}}_{\text{2}}-{\stackrel{\to }{d}}_{\text{1}}$?