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Triangle Side Calculator with Angles

Law of Sines:

\[ a = 2R \sin(A) \]

length units
degrees

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1. What is the Law of Sines?

The Law of Sines is a trigonometric formula relating the lengths of sides of a triangle to the sines of its opposite angles. It's useful for finding unknown sides or angles in any triangle.

2. How Does the Calculator Work?

The calculator uses the Law of Sines formula:

\[ a = 2R \sin(A) \]

Where:

Explanation: The formula calculates the length of a side when you know the triangle's circumradius and the angle opposite that side.

3. Importance of Triangle Side Calculation

Details: Calculating unknown sides of triangles is fundamental in geometry, trigonometry, and various applications like navigation, architecture, and physics.

4. Using the Calculator

Tips: Enter the circumradius in any length units and the angle in degrees. The result will be in the same units as the circumradius.

5. Frequently Asked Questions (FAQ)

Q1: What is a circumradius?
A: The radius of the circumscribed circle that passes through all three vertices of the triangle.

Q2: Can I use this for any triangle?
A: Yes, the Law of Sines applies to all triangles, whether acute, right, or obtuse.

Q3: What if my angle is in radians?
A: Convert radians to degrees first (1 radian ≈ 57.2958 degrees) or modify the code to handle radians.

Q4: How accurate is this calculation?
A: The calculation is mathematically exact, though practical accuracy depends on input precision.

Q5: Can I calculate the angle if I know the side?
A: Yes, you can rearrange the formula as \( A = \arcsin(a/(2R)) \), but this calculator focuses on side calculation.

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