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MHT CET20226 Aug 2022Evening ShiftMathematicsVector AlgebraActual

Let a = i -2 j + k and b = i - j + k be two vectors. If c is a vector such that b c = b a and c a then c b is equal to

Options

  1. A- 1 2
  2. B- 3 2
  3. C1 2
  4. D3 2

Correct answer

A. - 1 2

Step-by-step solution

aligned & b c = b a & b c - b a = 0 & b ( c - a )= 0 & c - a | b & c - a = b & c = a + b & c a =0 ( a + b ) a =0 a b + b a =0 & 11^2+(-2)^2+1^2+ (1 1+(-2) (-1)+1 1) & =- 3 2 aligned aligned & Now c b =( a + b ) b & = a b + b b & =4- 3 2 3=4- 9 2 =- 1 2 aligned

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