Question

The vector equations of two lines $L_1$ and $L_2$ are respectively
$\vec{r}=17\hat{i}-9\hat{j}+9\hat{k}+\lambda (3\hat{i}+\hat{j}+5\hat{k})$ and $\vec{r}=15\hat{i}-8\hat{j}-\hat{k}+\mu (4\hat{i}+3\hat{j})$
I $L_1$ and $L_2$ are skew lines
II $(11,-11,-1)$ is the point of intersection of $L_1$ and $L_2$
III $(-11,11,1)$ is the point of intersection of $L_1$ and $L_2$
IV ${\cos }^{-1}(3/\sqrt{35})$ is the acute angle between $L_1$ and $L_2$
then, which of the following is true?

• A. II and IV
• B. I and IV
• C. IV only
• D. III and IV

Answer 1

Answer: (A)

Correct answer is (a) II and IV