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MHT CET202211 Aug 2022Morning ShiftMathematicsVector AlgebraActual

If | a |=5,| b |=13 and | a b |=25 . If 2 < < where is angle between a , b then a b has the value

Options

  1. A-60
  2. B-30
  3. C60
  4. D30

Correct answer

A. -60

Step-by-step solution

aligned & | a b |=| a b | & 25=5 13 & = 5 13 & = -12 13 [ 2 < < ] & now a b =| a || b | =5 13 -12 13 =-60 aligned

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