cho mk xin 1 tick để mk tron 100 đi
mk se tick lai cho
\(81^7-27^9-9^{13}=3^{28}-3^{27}-3^{26}=3^{22}.\left(3^6-3^5-3^4\right)=3^{22}.405\)
=> Chia hết cho 405
817-279-913=(34)7-(33)9-(32)13=328-327-326=326.32-326.3-326=326.(32-3-1)=322.34.5=322.405 chia hết cho 405
Vậy 817-279-913 chia hết cho 405
tick nha