3-3 할리데이 10판 솔루션 일반물리학

$$\vec x = 15\ut{m}\hat i + 15\ut{m}\hat j + 10\ut{m}\hat k$$ $$x=?$$ $$ \begin{aligned} x&=\abs{\vec x}\\ &=\sqrt{15^2+15^2+10^2}\ut{m}\\ &=5\sqrt{22}\ut{m}\\ &\approx 23.45207879911715\ut{m}\\ &\approx 23\ut{m}\\ \end{aligned} $$