Vector Algebra Question 8
Question: If $ ai+6j-k $ and $ 7i-3j+17k $ are perpendicular vectors, then the value of a is
[Karnataka CET 2001]
Options:
A) 5
B) ? 5
C) 7
D) $ \frac{1}{7} $
Show Answer
Answer:
Correct Answer: A
Solution:
- We know that as the vectors are perpendicular, therefore their dot product is zero or $ (a\mathbf{i}+6\mathbf{j}-\mathbf{k}),.,(7\mathbf{i}-3\mathbf{j}+17\mathbf{k})=0 $ or $ 7a-18-17=0 $ or $ 7a=35 $ or $ a=5 $ .
BETA
