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MHT CET202123 Sep 2021Evening ShiftMathematicsVector AlgebraActual

If a = i +2 j +3 k , b =- +2 + k , c =3 i + j and a + b is perpendicular to c , then =

Options

  1. A5
  2. B2
  3. C3
  4. D4

Correct answer

A. 5

Step-by-step solution

aligned & ( a + b ) c =0 & [(1- ) i +(2+2 ) j +(3+ ) k ] [3 i + j ]=0 & (1- )(3)+(2+2 )(1)=0 =5 aligned

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