calculati ultima cifra :201^2018+7^2018+5^2018

Răspuns :

U(201^2018) = U(1^2018) = 1

2018 = 4 × 504 + 2

U ( 7^2018) = U( 7^2) = U ( 49) = 9

U ( 5^2018) = 5


U ( 201^2018+7^2018+5^2018) = U(1+9+5) =

= U (15) = 5
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