TeXipedia

arctg

Represents the inverse tangent (arctangent) function in mathematical expressions, returning angles in radians.

Overview

Serves as a fundamental inverse trigonometric function essential in mathematics and applied sciences, particularly when determining angles from ratios.

  • Common in coordinate transformations and navigation calculations
  • Used extensively in physics for analyzing periodic motion and waves
  • Appears frequently in engineering applications, especially in control systems and signal processing
  • Alternative to the more commonly used \arctan notation, particularly in European mathematical texts

Examples

Finding the angle in a right triangle given the ratio of sides.

θ=arctg(ab)\theta = \arctg\left(\frac{a}{b}\right)
\theta = \arctg\left(\frac{a}{b}\right)

Expressing the solution to a trigonometric equation.

x=arctg(2)+πn,nZx = \arctg(2) + \pi n,\quad n \in \mathbb{Z}
x = \arctg(2) + \pi n,\quad n \in \mathbb{Z}

Calculating the angle of intersection between two lines.

α=arctg(m1m21+m1m2)\alpha = \arctg\left(\left|\frac{m_1 - m_2}{1 + m_1m_2}\right|\right)
\alpha = \arctg\left(\left|\frac{m_1 - m_2}{1 + m_1m_2}\right|\right)