Vector Algebra Question 168
Question: If a and b are mutually perpendicular vectors, then $ {{(\mathbf{a}+\mathbf{b})}^{2}}= $
[MP PET 1994; Pb. CET 2002]
Options:
A) $ \mathbf{a}+\mathbf{b} $
B) $ \mathbf{a}-\mathbf{b} $
C) $ a^{2}-b^{2} $
D) $ {{(\mathbf{a}-\mathbf{b})}^{2}} $
Show Answer
Answer:
Correct Answer: D
Solution:
- It is obvious, since $ \mathbf{a},.,\mathbf{b}=0. $ Hence $ {{(\mathbf{a}+\mathbf{b})}^{2}}=a^{2}+b^{2}={{(\mathbf{a}-\mathbf{b})}^{2}}. $
BETA
