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MHT CET202210 Aug 2022Evening ShiftMathematicsVector AlgebraActual

If the points A(3,2,1), B(4, x, 5), C(4,2,-2) and D(6,5,-1) are coplanar, then x has the value

Options

  1. A-5
  2. B5
  3. C-6
  4. D6

Correct answer

B. 5

Step-by-step solution

For coplanarity aligned & [ array ccc 6-3 & 5-2 & -1-1 4-3 & x-2 & 5-1 4-3 & 2-2 & -2-1 array ]=0 & [ array ccc 3 & 3 & -2 1 & x-2 & 4 1 & 0 & -3 array ]=0 & 3 -3(x-2)-0 -3 1 (-3)-1 4 -2(1 0-1 (x-2))=0 & -7 x+35=0 & x=5 aligned

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