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MHT CET202121 Sep 2021Morning ShiftMathematicsVector AlgebraActual

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

Options

  1. A-14
  2. B14
  3. C2
  4. D-2

Correct answer

A. -14

Step-by-step solution

From given data, we write a + b =(2- ) i +(2+2 ) j +(3+ ) k Since (1) is er to c , we write aligned & (2- )(3)+(2+2 )(1)+(3+ )(2)=0 & 6-3 +2+2 +6+2 =0 =-14 aligned

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