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How to Calculate Octahedron

What is Octahedron?

A regular octahedron is one of the five Platonic solids, with 8 equilateral triangular faces, 12 edges, and 6 vertices. It looks like two square pyramids joined at the base.

Formula

V = (√2/3)a³; SA = 2√3 a²
a
edge length (length)
V
volume (length³)
SA
surface area (length²)

Step-by-Step Guide

  1. 1Volume = (√2/3) × a³
  2. 2Surface area = 2√3 × a²
  3. 3Face diagonal = a√2
  4. 4Height = a√2

Worked Examples

Input
Edge a = 4
Result
Volume ≈ 30.17, SA ≈ 55.42
Input
Edge a = 6
Result
Volume ≈ 101.82, SA ≈ 124.71

Frequently Asked Questions

Why is the octahedron called a Platonic solid?

It's one of five Platonic solids: all faces are congruent regular polygons, and the same number of faces meet at each vertex.

How many vertices, edges, and faces does an octahedron have?

The octahedron has 6 vertices, 12 edges, and 8 equilateral triangular faces.

What is the dual polyhedron of an octahedron?

The cube (hexahedron) is the dual. Its vertices correspond to the octahedron's face centers.

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