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Find the value of a for which the vectors  are collinear?

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

Answer (Detailed Solution Below)

Option 2 : - 4
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Detailed Solution

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CONCEPT:

For two vectors  to be collinear,​  where λ is a scalar.

CALCULATION:

Given: The vectors  are collinear.

As we know that, if two vectors  are collinear then  where λ is a scalar.

⇒ 

⇒ 

⇒ λa = 2 and 6λ = - 3

⇒  λ = -1/2

So, by substituting λ = -1/2 in the equation λa = 2 we get

⇒ a = 2 × - 2 = - 4

Hence, option B is the correct answer.

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