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Find the value of λ for which the vectors  and  are perpendicular ?

  1. - 9
  2. 9
  3. - 3
  4. 3

Answer (Detailed Solution Below)

Option 1 : - 9
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Detailed Solution

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CONCEPT:

If vectors  are perpendicular then 

CALCULATION:

Given:  and  are perpendicular

∵  and  are perpendicular

⇒ λ + 9 = 0

⇒ λ = - 9

Hence, option A is the correct answer.

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