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COMEDK2017MathematicsHeights and Distances

Let (3,4,-1) and (-1,2,3) be the end points of a diameter of a sphere. Then, the radius of the sphere is equal to

Options

  1. A2 units
  2. B3 units
  3. C6 units
  4. D7 units

Correct answer

B. 3 units

Step-by-step solution

Let P(3,4,-1) and Q(-1,2,3) be the end points of the diameter of a sphere. Length of diameter =P Q aligned &= (-1-3)²+(2-4)²+(3+1)² &= 16+4+16 = 36 =6 units Radius &= 6 2 =3 units aligned

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