Find the angle between the following vectors: A = i + j - k B = i - j + k |
\(\cos^{-1} \left(\frac{2}{3}\right)\) \(\sin^{-1} \left(\frac{2}{3}\right)\) \(\cos^{-1} \left(\frac{-1}{3}\right)\) \(\sin^{-1} \left(\frac{1}{3}\right)\) |
\(\cos^{-1} \left(\frac{-1}{3}\right)\) |
\(\begin{aligned}\cos \theta &=\frac{(\hat{i}+\hat{j}-\hat{k})\cdot (\hat{i}-\hat{j}+\hat{k})}{\sqrt{3}\cdot \sqrt{3}}\\ &=-\frac{1}{3}\\ \theta &=\cos^{-1}\left(-\frac{1}{3}\right)\end{aligned}\) |