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The position vectors of the points A and B are respectively 3î - 5ĵ + 2k̂ and î + ĵ - k̂. What is the length of AB?

  1. 11
  2. 9
  3. 7
  4. 6

Answer (Detailed Solution Below)

Option 3 : 7
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Detailed Solution

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Concept:

Let  then the magnitude of the vector of  = 

Calculation:

Given:

Position vectors of the points A and B are respectively 3î - 5ĵ + 2k̂ and î + ĵ - k̂

⇒   (î + ĵ - k̂) - (3î - 5ĵ + 2k̂)

Now, the length of 

⇒  = 

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