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MHT CET202123 Sep 2021Evening ShiftMathematicsVector AlgebraActual

If â is a unit vector such that ( x - a ) ( x + a )=8 , then | x |=

Options

  1. A3
  2. B2 2
  3. C3
  4. D7

Correct answer

C. 3

Step-by-step solution

We have ( x - a ) ( x + a )=8 | x |^2-| a |^2=8 | x |^2=8+1=9 | x |=3

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