Vector Algebra Question 89
Question: If $ \mathbf{a}=2\mathbf{i}+2\mathbf{j}-\mathbf{k} $ and $ |x,\mathbf{a}|=1, $ then x =
Options:
A) $ \pm \frac{1}{3} $
B) $ \pm \frac{1}{4} $
C) $ \pm \frac{1}{5} $
D) $ \pm \frac{1}{6} $
Show Answer
Answer:
Correct Answer: A
Solution:
- $ |x\mathbf{a}|=|x||\mathbf{a}|\Rightarrow |x|\sqrt{4+4+1}=1 $
$ \Rightarrow x=\pm \frac{1}{3}. $
BETA
