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MHT CET20228 Aug 2022Evening ShiftMathematicsVector AlgebraActual

The value of a , so that the volume of parallelepiped formed by i +a j + k , j +a k and a i + k becomes minimum is

Options

  1. A1 3
  2. B3
  3. C-3
  4. D3

Correct answer

A. 1 3

Step-by-step solution

Volume of parallelepiped = | array lll 1 & a & 1 0 & 1 & a a & 0 & 1 array |=a^3-a+1=V(a) Now V^ (a)=3 a^2-1 + . 1 - ₁^1+ 1 3 1 3 volume is minimum at x= 1 3

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