GeoGebra does not support complex numbers directly, but you may use points to simulate operations with complex numbers.
Example:
If you enter the complex number 3 + 4i into the Input
Bar,
you get the point
(3, 4) in the Graphics
View.
This points coordinates are shown as 3 +
4i in the Algebra View.
Note: You can display any point as a complex number in the Algebra View. Open the Properties Dialog for the point and select Complex Number from the list of Coordinates formats on tab Algebra.
If the variable i has not already been defined, it is recognized as the ordered pair i = (0, 1) or the complex number 0 + 1i. This also means, that you can use this variable i in order to type complex numbers into the Input Bar (e. g., q = 3 + 4i).
Addition and subtraction examples:
· (2 + 1i) + (1 2i) gives you the complex number 3 1i.
· (2 + 1i) - (1 2i) gives you the complex number 1 + 3i.
Multiplication and division examples:
· (2 + 1i) * (1 2i) gives you the complex number 4 3i.
· (2 + 1i) / (1 2i) gives you the complex number 0 + 1i.
Note: The usual multiplication (2, 1)*(1, -2) gives you the scalar product of the two vectors.
Other examples:
GeoGebra also recognizes expressions involving real and complex numbers.
· 3 + (4 + 5i) gives you the complex number 7 + 5i.
· 3 - (4 + 5i) gives you the complex number -1 - 5i.
· 3 / (0 + 1i) gives you the complex number 0 - 3i.
· 3 * (1 + 2i) gives you the complex number 3 + 6i.