Logarithm of complex number

Calculator for calculating the natural logarithm (log) of a complex number


The calculator on this page returns the natural logarithm (base e) of a specified complex number. To calculate, enter a complex number and then click the Calculate button.


Logarithm calculator

 Input
Complex number +  i
Decimal places
 Results
Logarithm

Formulas for calculation of the logarithm


In the following description,\(z\) stands for the complex number.
\(x\) stands for the real value \(Re\) and \(y\) for the imaginary value \(Im\).

\(\displaystyle ln(z) = \frac{1}{2} · ln\left(x^2 + y^2\right) + atan\left(\frac{y}{x}\right)\)

Example


\(ln(z) = ln(3+5i)\)

\(\displaystyle Re = \frac{1}{2} · ln\left(3^2 + 5^2\right) = \frac{1}{2} · ln(9 + 25) =1.763\)

\(\displaystyle Im = atan\left(\frac{5}{3}\right) = 1.030\)

\(\displaystyle ln(3+5i) = 1.763+1.030i\)

The result for \(\displaystyle Im \) is given in radians.

More complex functions

Absolute value (abs)AngleConjugateDivisionExponentLogarithm to base 10MultiplicationNatural logarithmPolarformPowerRootReciprocalSquare root
CoshSinhTanh
AcosAsinAtanCosSinTan
Airy functionDerivative Airy function
Bessel-IBessel-IeBessel-JBessel-JeBessel-KBessel-KeBessel-YBessel-Ye

Is this page helpful?            
Thank you for your feedback!

Sorry about that

How can we improve it?