Question Number 164940 by amin96 last updated on 23/Jan/22
$$−−−−−−−−− \\ $$$$\mathrm{1}!−\mathrm{2}!+\mathrm{3}!−\mathrm{4}!+\mathrm{5}!−\ldots−\mathrm{14}!+\mathrm{15}!=? \\ $$$$ \\ $$$$−−−−−−−−−−\boldsymbol{{by}}\:\boldsymbol{{M}}.\boldsymbol{{A}} \\ $$
Commented by MJS_new last updated on 24/Jan/22
$$\mathrm{just}\:\mathrm{type}\:\mathrm{into}\:\mathrm{any}\:\mathrm{calculator} \\ $$