Question Number 173917 by Michaelfaraday last updated on 21/Jul/22
$${prove}: \\ $$$$\left(−\mathrm{1}\right)! \\ $$
Commented by Frix last updated on 21/Jul/22
$$\mathrm{I}\:\mathrm{promise}\:\mathrm{to}\:\mathrm{prove}\:\left(−\mathrm{1}\right)!\:\mathrm{if}\:\mathrm{you}\:\mathrm{prove}\:\frac{\pi}{\mathrm{7}}. \\ $$
Commented by Michaelfaraday last updated on 01/Aug/22
$${okay}\:{but}\:{i}\:{do} {t}\:{know}\:{it} \\ $$