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Octagon Calculator Sides

Octagon Side Length Formula:

\[ s = 2 \times r \times \sin(\pi/8) \]

Where:
s = side length (length units)
r = radius (length units)

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1. What is the Octagon Side Length Formula?

The octagon side length formula calculates the length of each side of a regular octagon (8-sided polygon) given the radius (distance from center to vertex). The formula is derived from trigonometric relationships in regular polygons.

2. How Does the Calculator Work?

The calculator uses the octagon side length formula:

\[ s = 2 \times r \times \sin(\pi/8) \]

Where:

Explanation: The formula comes from dividing the octagon into 16 right triangles and using trigonometric sine function to calculate half of a side length.

3. Importance of Octagon Calculations

Details: Calculating octagon dimensions is essential in architecture, engineering, and design where octagonal shapes are used in structures, tiles, and various decorative elements.

4. Using the Calculator

Tips: Enter the radius (distance from center to any vertex) in any length units. The calculator will return the side length in the same units.

5. Frequently Asked Questions (FAQ)

Q1: What is a regular octagon?
A: A regular octagon is an eight-sided polygon with all sides equal in length and all angles equal in measure (135° each).

Q2: What's the difference between radius and apothem?
A: Radius is the distance from center to vertex, while apothem is the distance from center to midpoint of a side. They're related but different measurements.

Q3: Can I calculate area with this?
A: Not directly, but once you have the side length, you can calculate area using \( \text{Area} = 2(1+\sqrt{2}) \times s^2 \).

Q4: How accurate is this calculation?
A: The calculation is mathematically exact for a perfect regular octagon. Real-world measurements may vary due to construction tolerances.

Q5: What if my octagon isn't regular?
A: This formula only works for regular octagons. Irregular octagons require different calculation methods.

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