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KCET2022MathematicsVector Algebra

If | a b |^2+| a b |^2=36 and | a |=3 , then | a | is equal to

Options

  1. A9
  2. B36
  3. C4
  4. D2

Correct answer

D. 2

Step-by-step solution

Given, | a b |+| a b |^2=36 and | a |=3 Correct one is | a b |^2+| a b |^2=36 and | a |=3 We know, | a b |^2+| a b |^2=| a |^2| b |^2 array ll & | a |^2| b |^2=36 (3)^2| b |^2=36 & |b|^2=4 |b|=2 array Hence, the correct option is (4).

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