MCQ
If $a$  and $ b$ are mutually perpendicular vectors, then ${(a + b)^2} = $
  • A
    $a + b$
  • B
    $a - b$
  • C
    $a^2 -b^2$
  • ${(a - b)^2}$

Answer

Correct option: D.
${(a - b)^2}$
d
(d) It is obvious, since $a\,.\,b = 0.$

Hence ${(a + b)^2} = {a^2} + {b^2} = {(a - b)^2}.$

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