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MHT CET20225 Aug 2022Evening ShiftMathematicsVector AlgebraActual

If | a |=5,| b |=3,| c |=4 and a is perpendicular to b and c such that angle between b and c is 5 6 , then [ a b c ]=

Options

  1. A25
  2. B10
  3. C30
  4. D20

Correct answer

C. 30

Step-by-step solution

[ a b c ]=| a || b || c | ( of angle between a and b c ) .(sin of angle between b and c ) aligned & =5 3 4 0 ( 5 6 ) & =60 1 1 2 =30 aligned

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