$$$\frac{2}{7}\cdot \left\langle 3, 1, 2\right\rangle$$$

$$$\frac{2}{7}\cdot \left\langle 3, 1, 2\right\rangle$$$を計算せよ。

ベクトルの各成分にスカラーを乗じる:

$$${\color{Peru}\left(\frac{2}{7}\right)}\cdot \left\langle 3, 1, 2\right\rangle = \left\langle {\color{Peru}\left(\frac{2}{7}\right)}\cdot \left(3\right), {\color{Peru}\left(\frac{2}{7}\right)}\cdot \left(1\right), {\color{Peru}\left(\frac{2}{7}\right)}\cdot \left(2\right)\right\rangle = \left\langle \frac{6}{7}, \frac{2}{7}, \frac{4}{7}\right\rangle$$$

$$$\frac{2}{7}\cdot \left\langle 3, 1, 2\right\rangle = \left\langle \frac{6}{7}, \frac{2}{7}, \frac{4}{7}\right\rangle\approx \left\langle 0.857142857142857, 0.285714285714286, 0.571428571428571\right\rangle$$$A