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Question Number 206025 by cortano12 last updated on 05/Apr/24

     2^(2024)  = x (mod 10)

22024=x(mod10)

Answered by BaliramKumar last updated on 05/Apr/24

Find unit digit  2^(2024)  = 2^(4k + 4)  = 2^4   = 16 ⇒ 6

Findunitdigit22024=24k+4=24=166

Answered by Rasheed.Sindhi last updated on 05/Apr/24

     2^(2024)  = x (mod 10)      2^4 ≡6(mod 10)   2^(2024)  ≡ x (mod 10)  ⇒2^(4×506) ≡x(mod 10)  ⇒(2^4 )^(506) ≡x(mod 10)  ⇒(6)^(506) ≡x(mod 10)  Observe that 6^k ≡6(mod 10) ∀k∈N  ∴ 6^(506) ≡6 (mod 10)  ∴ (2^4 )^(506) ≡6 (mod 10)  ∴ 2^(2024) ≡6(mod 10)

22024=x(mod10)246(mod10)22024x(mod10)24×506x(mod10)(24)506x(mod10)(6)506x(mod10)Observethat6k6(mod10)kN65066(mod10)(24)5066(mod10)220246(mod10)

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