Question

Aflați ultima cifra a numerelor:2la puterea 17; 3 la puterea 19;8la puterea 7;7la puterea 95;5 la puterea 132

Answer 1

17 = 4 × 4 + 1

U ( 2^17) = U ( 2^1) = 2
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19 = 4 × 4 + 3

U ( 3^19) = U ( 3^3) = U ( 27) = 7
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7 = 4 × 1 + 3

U (8^7) = U ( 8^3) = U ( 512) = 2
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95 = 4 × 23 + 3

U ( 7^95) = U ( 7^3) = U ( 343) = 3
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U ( 5^132) =5

trebuie sa stii ca 5 ridicat la orice putere, intotdeauna are ultima cifra 5
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