Vector Algebra Question 390
Question: If the vectors $ a,\mathbf{i}-2\mathbf{j}+3\mathbf{k} $ and $ 3\mathbf{i}+6\mathbf{j}-5\mathbf{k} $ are perpendicular to each other, then a is given by
[MP PET 1993]
Options:
A) 9
B) 16
C) 25
D) 36
Show Answer
Answer:
Correct Answer: A
Solution:
- Obviously, $ 3a-12-15=0\Rightarrow a=9. $
BETA
