3-10 할리데이 10판 솔루션 일반물리학

$$\begin{cases} \vec c = \(7.4 \)\hat i + \(-3.8 \)\hat j + \(-6.1 \)\hat k\\ \vec d = \(4.4 \)\hat i + \(-2.0 \)\hat j + \(3.3 \)\hat k\\ \end{cases} $$ $$ \begin{aligned} \vec r &= \(7.4+4.4 \)\hat i + \(-3.8-2.0 \)\hat j + \(-6.1+3.3 \)\hat k\\ &=\(11.8 \)\hat i + \(-5.8 \)\hat j + \(-2.8 \)\hat k \end{aligned} $$
(a)$r_x=11.8$
(b)$r_y=-5.8$
(c)$r_z=-2.8$