Question

If the vectors $\overrightarrow{a} =\lambda \hat{i}+\mu\hat{j}+4\hat{k}$, $\overrightarrow{b}=-2\hat{i}+4\hat{j}-2\hat{k}$ and $\overrightarrow{c}=2\hat{i}+3\hat{j}+\hat{k}$ are coplanar and the projection of $\overrightarrow{a}$ on the vector $\overrightarrow{b}$ is $\sqrt{54}$ units, then the sum of all possible values of $\lambda + \mu$ is equal to

• A. 24
• B. 6
• C. 0
• D. 18

Answer 1

Answer: (A)

24

Answer 2

The correct answer is 24