Im[z] gives the imaginary part of the complex number z.

You can enter complex numbers in Mathematica just by including the constant I, equal to Sqrt[-1]. Make sure that you type a capital I. If you are using notebooks, you can ...

Mathematica usually pays no attention to whether variables like x stand for real or complex numbers. Sometimes, however, you may want to make transformations which are ...

Mathematica transparently works with complex variables throughout, not only numerically, but also symbolically—often relying on original results to handle intricate branch ...

Mathematica has fundamental support for both explicit complex numbers and symbolic complex variables. All applicable mathematical functions support arbitrary-precision ...

Functions relating real numbers and integers. Extracting integer and fractional parts. IntegerPart[x] and FractionalPart[x] can be thought of as extracting digits to the left ...

Mathematica has the most extensive collection of mathematical functions ever assembled. Often relying on original results and algorithms developed at Wolfram Research over ...

Complexes represents the domain of complex numbers, as in x \[Element] Complexes.

The complete collection of Greek letters in Mathematica. You can use Greek letters as the names of symbols. The only Greek letter with a built-in meaning in StandardForm is ...

ComplexExpand[expr] expands expr assuming that all variables are real. ComplexExpand[expr, {x_1, x_2, ...}] expands expr assuming that variables matching any of the x_i are ...