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Complex addition and multiplication (integral)

Complex Numbers

An integral complex number is a number of the form $a+i\cdot b$ where the real part $a$ and the imaginary part $b$ are both integers. Addition and multiplication of integral complex numbers results in an integral complex number.

In the following applets, the numbers $a$ and $b$ can be moved to integral grid points.


Complex Addition

Please enable Java for an interactive construction (with Cinderella).

Complex Addition follows the rule

\[ (a_1+ib_1)+(a_2+ib_2)=(a_1+a_2)+i(b_1+b_2). \]


Complex Multiplication

Please enable Java for an interactive construction (with Cinderella).

Complex Multiplication follows the rule

\[ (a_1+ib_1)(a_2+ib_2)=(a_1b_1-a_2b_2)+i(a_1b_2+a_2b_1). \]


Both operation can be easily deduced by interpreting $i$ as a unit (of measure), simplyfying the equation as usual, but taking the special rule $i^2=-1$ into account.


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Inversion $\hookleftarrow$ Contents $\hookrightarrow$ Complex addition and multiplication (generic)