Inverse Tangent (Arctan) Calculator Formula

Understand the math behind the inverse tangent (arctan) calculator. Each variable explained with a worked example.

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Formulas Used

Angle Rad

angle_rad = atan(val)

Angle Deg

angle_deg = atan(val) * 180 / pi

Variables

VariableDescriptionDefault
valValue1

How It Works

Inverse Tangent (Arctan)

Definition

arctan(x) = the angle whose tangent is x

Domain and Range

  • Domain: all real numbers
  • Range: -90° to 90° (-pi/2 to pi/2 radians)

    • Unlike arcsin and arccos, arctan accepts any real number as input.

    Worked Example

    Find arctan(1).

    val = 1
    1. 01arctan(1) = pi/4 radians
    2. 02= 45 degrees
    3. 03Verification: tan(45°) = 1

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