COMPLEX NUMBER
\kˈɒmplɛks nˈʌmbə], \kˈɒmplɛks nˈʌmbə], \k_ˈɒ_m_p_l_ɛ_k_s n_ˈʌ_m_b_ə]\
Definitions of COMPLEX NUMBER
 2006  WordNet 3.0
 2011  English Dictionary Database
 1985  The Free Online Dictionary of Computing
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By Princeton University
By DataStellar Co., Ltd

A number of the form x+iy where i is the squareroot of 1, and x and y are real numbers, known as the"real" and "imaginary" part. Complex numbers can be plottedas points on a twodimensional plane, known as an Arganddiagram, where x and y are the Cartesian coordinates.An alternative, polar notation, expresses a complex numberas (r e^it) where e is the base of natural logarithms, and rand t are real numbers, known as the magnitude and phase. Thetwo forms are related:r e^it = r cos(t) + i r sin(t) = x + i ywherex = r cos(t)y = r sin(t)All solutions of any polynomial equation can be expressed ascomplex numbers. This is the socalled Fundamental Theoremof Algebra, first proved by Cauchy.Complex numbers are useful in many fields of physics, such aselectromagnetism because they are a useful way of representinga magnitude and phase as a single quantity.
By Denis Howe
Word of the day
Pyrrolidinones
 A compounds that are derivatives oxopyrrolidines. member this group 2oxo pyrrolidine, which is an intermediate in the manufacture of polyvinylpyrrolidone. (From Merck Index, 11th ed)