The real part of a Complex Number is the Real Number not multiplying i, so
. In terms of itself,
See also Absolute Square, Complex Conjugate, Imaginary Part
Abramowitz, M. and Stegun, C. A. (Eds.).
Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables, 9th printing.
New York: Dover, p. 16, 1972.