Editing Lambert W function (section)

== Terminology ==
The notation convention chosen here (with {{math|''W''<sub>0</sub>}} and {{math|''W''<sub>−1</sub>}}) follows the canonical reference on the Lambert {{mvar|W}} function by Corless, Gonnet, Hare, Jeffrey and [[Donald Knuth|Knuth]].<ref name="Corless">
{{cite journal
 | last1 = Corless
 | first1 = R. M.
 | last2 = Gonnet
 | first2 = G. H.
 | last3 = Hare
 | first3 = D. E. G.
 | last4 = Jeffrey
 | first4 = D. J.
 | last5 = Knuth
 | first5 = D. E.
 | title = On the Lambert {{mvar|W}} function
 | journal = Advances in Computational Mathematics
 | pages = 329–359
 | year = 1996
 | volume = 5
 | url = https://cs.uwaterloo.ca/research/tr/1993/03/W.pdf
 | doi = 10.1007/BF02124750 | s2cid = 29028411
}}</ref>

The name "product logarithm" can be understood as follows: since the [[inverse function]] of {{math|1=''f''(''w'') = ''e''<sup>''w''</sup>}} is termed the [[logarithm]], it makes sense to call the inverse "function" of the [[Product (mathematics)|product]] {{math| ''we''<sup>''w''</sup>}} the "product logarithm". (Technical note: like the [[complex logarithm]], it is multivalued and thus W is described as a [[converse relation]] rather than inverse function.) It is related to the [[omega constant]], which is equal to {{math|''W''<sub>0</sub>(1)}}.