arctan(0) = 0°
The arctangent of 0 is 0 degrees.
The arctangent function (arctan or tan⁻¹) is the inverse of the tangent function. It takes any real number and returns the angle (in degrees) whose tangent is that value. Unlike arcsine and arccosine, arctangent accepts any numeric value and always returns an angle between -90° and 90°. This calculator provides instant and accurate arctangent calculations for mathematical, scientific, and engineering applications.
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Mathematical Explanation
Arctangent is the inverse tangent function: if tan(θ) = x, then arctan(x) = θ. The domain is all real numbers (-∞, ∞) and the range is (-90°, 90°). Common values: arctan(0) = 0°, arctan(1) = 45°, arctan(√3) ≈ 60°. The function is also written as tan⁻¹(x) or atan(x). As the input approaches ±∞, the output approaches ±90° asymptotically.Frequently Asked Questions
The arctangent function (arctan or tan⁻¹) is the inverse of the tangent function. It takes any real number and returns the angle whose tangent equals that value. For example, arctan(1) = 45° because tan(45°) = 1. Unlike arcsine and arccosine, arctangent can accept any numeric value.
arctan(1) equals 45 degrees exactly. This is one of the fundamental inverse trigonometric values that appears frequently in mathematics and engineering, representing the angle of a 45-45-90 triangle.
arctan(√3) equals 60 degrees. This value corresponds to the tangent of a 60° angle in a 30-60-90 triangle, where the opposite side is √3 times the adjacent side.
The arctangent function can accept any real number because the tangent function produces all real numbers as its range. As angles approach ±90°, tangent approaches ±∞, which means arctangent can convert any real number back to an angle between -90° and 90°.
This calculator returns angles in degrees. If you need the result in radians, multiply the degree value by π/180. For reference, 45° = π/4 radians and 60° = π/3 radians.
Resources & References
Encyclopedia Resources
- Inverse Trigonometric Functions - Wikipedia - Comprehensive guide to arctangent and other inverse trigonometric functions
- Trigonometry - Wikipedia - Learn about trigonometric functions and their inverses
Educational Resources
- Khan Academy - Inverse Trigonometry - Free inverse trigonometry lessons and practice problems
- Math is Fun - Inverse Tangent - Interactive arctangent examples and explanations