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MHT CET202124 Sep 2021Morning ShiftMathematicsDeterminantsActual

If A= [ array ccc 5 & 6 & 3 -4 & 3 & 2 -4 & -7 & 3 array ] , then cofactors of all elements of second row are respectively.

Options

  1. A-39,3,11
  2. B-39,27,11
  3. C39,-3-11
  4. D-39,-27,11

Correct answer

B. -39,27,11

Step-by-step solution

A= [ array ccc 5 & 6 & 3 -4 & 3 & 2 -4 & -7 & 3 array ] Cofactors of elements in second row are Cofactor of -4 Cofactor of 3 aligned & =(-1)²⁺¹ | array cc 6 & 3 -7 & 3 array |=-(18+21)=-39 & =(-1)²⁺² | array cc 5 & 3 -4 & 3 array |=15+12=27 & =(-1)²⁺³ | array cc 5 & 6 -4 & -7 array |=-(-35+24)=11 aligned

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