2 câu trả lời
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Ta có:
20152≡1(mod
=> 2015^2014 ≡ 1 (mod 8)
Lại có:
2015 ≡ 7 (mod 8)
=> 2015^2014 . 2015 ≡ 1 . 7 (mod 8)
=> 2015^2015 ≡ 7 (mod 8)
Vậy 2015^2015 chia 8 dư 7
2015^2≡1(mod 8)
=> 2015^{2014}≡1(mod 8)
2015≡7(mod 8)
=>2015^{2015}≡7(mod 8)
=>2015^{2015} chia 8 dư 7