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NDA2021MathematicsThree Dimensional GeometryActual

The number of spheres of radius r touching the coordinate axes is

Options

  1. A4
  2. B6
  3. C8
  4. Dinfinite

Correct answer

C. 8

Step-by-step solution

There are 8 octants in coordinate system so, 8 spheres of radius r touching the coordinate axes.

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