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Calculating Angle of Right Triangle

Right Triangle Angle Formula:

\[ \theta = \arctan\left(\frac{\text{opposite}}{\text{adjacent}}\right) \]

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1. What is the Right Triangle Angle Formula?

The right triangle angle formula calculates an angle θ using the arctangent of the ratio of the opposite side to the adjacent side. This is one of the fundamental trigonometric relationships in right triangles.

2. How Does the Calculator Work?

The calculator uses the arctangent formula:

\[ \theta = \arctan\left(\frac{\text{opposite}}{\text{adjacent}}\right) \]

Where:

Explanation: The arctangent function converts the ratio of opposite to adjacent sides into an angle measurement.

3. Importance of Angle Calculation

Details: Calculating angles in right triangles is essential in geometry, trigonometry, engineering, physics, and many practical applications like construction and navigation.

4. Using the Calculator

Tips: Enter lengths of the opposite and adjacent sides in any consistent units. Select whether you want the result in degrees or radians. Both side lengths must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What if I know the hypotenuse instead?
A: You can use arcsine (opposite/hypotenuse) or arccosine (adjacent/hypotenuse) instead of arctangent.

Q2: What's the range of possible angles?
A: In a right triangle, the non-right angles range between 0° and 90° (0 to π/2 radians).

Q3: How accurate is this calculation?
A: The calculation is mathematically exact, though practical measurements of sides may introduce error.

Q4: Can I use this for non-right triangles?
A: No, this formula only works for right triangles. For other triangles, use the Law of Cosines.

Q5: Why choose degrees vs radians?
A: Degrees are more common in everyday applications, while radians are typically used in higher mathematics and physics.

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