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JEE Main20252 Apr 2025Morning ShiftMathematicsVector AlgebraActual

Let A B C D be a tetrahedron such that the edges AB , AC and AD are mutually perpendicular. Let the areas of the triangles ABC , ACD and ADB be 5,6 and 7 square units respectively. Then the area (in square units) of the BCD is equal to :

Options

  1. A340
  2. B12
  3. C110
  4. D7 3

Correct answer

C. 110

Step-by-step solution

Ar ( B C D) = ( Ar ( ABC ))^2+( Ar ( ACD ))^2+( Ar ( ADB ))^2 = 5^2+6^2+7^2 = 110

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