Question Number 160739 by SANOGO last updated on 05/Dec/21
$$\:{nature}\:{de}\:{cette}\:{integrale}\:{quequ}'{en}\:{soit}\:{le}\:{reel}\:\alpha \\ $$$$\int_{\mathrm{1}} ^{+{oo}} {t}^{\alpha} {e}^{−{t}} {dt} \\ $$
Commented by SANOGO last updated on 05/Dec/21
$${demonstration} \\ $$
Commented by yeti123 last updated on 05/Dec/21
$$\Gamma\left(\alpha+\mathrm{1},\:\mathrm{1}\right) \\ $$
Commented by SANOGO last updated on 06/Dec/21
$${demonstration}\:{svp} \\ $$