Definition:Complex Number/Imaginary Unit
The entity $i := 0 + 1 i$ is known as the imaginary unit.
Also denoted as
The non-italicized $\mathrm i$ can also be seen.
- 1960: Walter Ledermann: Complex Numbers ... (previous) ... (next): $\S 1.1$. Number Systems
- 1968: Murray R. Spiegel: Mathematical Handbook of Formulas and Tables ... (previous) ... (next): $6$: Complex Numbers
- 1981: Murray R. Spiegel: Theory and Problems of Complex Variables (SI ed.) ... (previous) ... (next): $1$: Complex Numbers: The Complex Number System