Question
Question: If **a** and **b** are mutually perpendicular vectors, then \((\mathbf{a} + \mathbf{b})^{2} =\)...
If a and b are mutually perpendicular vectors, then (a+b)2=
A
a+b
B
a−b
C
a2−b2
D
(a−b)2
Answer
(a−b)2
Explanation
Solution
It is obvious, since a.b=0.
Hence (a+b)2=a2+b2=(a−b)2.