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MHT CET20225 Aug 2022Morning ShiftMathematicsVector AlgebraActual

Let a , b , c be vectors of lengths 3,4,5 respectively. Let a be perpendicular to b + c , b be perpendicular to c + a and c be perpendicular to a + b , then the length of vector a + b + c is

Options

  1. A5
  2. B5 3
  3. C5 2
  4. D5 6

Correct answer

C. 5 2

Step-by-step solution

aligned & Now | a + b + c |= | a |^2+| b |^2+| c |^2+2 a b +2 b c +2 c a & = 3^2+4^2+5^2+0 [ | a |=3,| b |=4,| c |=5 given and from(iv) & = 50 & =5 2 aligned

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