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MHT CET202121 Sep 2021Evening ShiftMathematicsVector AlgebraActual

If 2 < and | a |=5,| b |=13,| a b |=25 , then the value of a b is

Options

  1. A-12
  2. B60
  3. C-60
  4. D-13

Correct answer

C. -60

Step-by-step solution

aligned & | a b |=25 & | a | | b | =(5)(13) =25 & = 5 13 = -12 13 & a b =| a | | b | & =(5)(13) ( -12 13 )=-60 aligned

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