Question

If $\theta$ denotes the acute angle between the line $\vec{r}=((\hat{i}+2\hat{j}-\hat{k})+\lambda (\hat{i}-\hat{j}+\hat{k})$ and the plane $\vec{r}\cdot (2\hat{i}-\hat{j}+\hat{k})=4,$ then $\sin \theta +\sqrt{2}\cos \theta =$

• A. $1/\sqrt{2}$
• B. $\sqrt{2}-1$
• C. $\sqrt{2}$
• D. $1+\sqrt{2}$

Answer 1

Answer: (C)

Correct answer is (c) $\sqrt{2}$