Question Number 179031 by sciencestudent last updated on 23/Oct/22
$${prove}\:{that}\:{sgn}\left(\mathrm{0}\right)=\mathrm{0} \\ $$
Commented by MJS_new last updated on 23/Oct/22
$$\mathrm{no}\:\mathrm{proof}\:\mathrm{possible},\:\mathrm{it}'\mathrm{s}\:\mathrm{a}\:\mathrm{definition} \\ $$