i: the imaginary unit

i is the imaginary unit, defined by i² = −1. It extends real arithmetic to complex numbers and is fundamental in electrical engineering, waves, and quantum mechanics.

Using complex values

Combine i with real coefficients, then inspect components with re() and im(). Use conj() for complex conjugation and abs() for magnitude.

Caveat

Do not confuse i with a variable name in expressions where a different symbol has been assigned.