Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Bạn alibaba nguyễn sai rồi nên mình sửa lại rồi bạn xem nhé :
Lời giải :
Ta có : \(331\equiv1\left(mod15\right)\)
\(\Rightarrow331^{332}\equiv1^{332}\equiv1\left(mod15\right)\left(1\right)\)
Ta có : \(2^4\equiv1\left(mod15\right)\)
\(\Rightarrow2^{333}=\left(2^4\right)^{83}.2\equiv2\left(mod15\right)\)
\(\Rightarrow332^{333}\equiv2^{333}\equiv2\left(mod15\right)\left(2\right)\)
Ta có : \(3^5\equiv3\left(mod15\right)\)
\(\Rightarrow3^{334}=3^{5.66}.3^4\equiv3^{66}.3^4\equiv3^{70}\equiv\left(3^5\right)^{14}\equiv3^{14}\equiv\left(3^5\right)^2.3^4\equiv3^2.3^4\equiv3^6\equiv9\left(mod15\right)\)
\(\Rightarrow333^{334}\equiv3^{334}\equiv9\left(mod15\right)\left(3\right)\)
Từ ( 1 ) , ( 2 ) , ( 3 ) suy ra : \(A\equiv\left(1+2+9\right)\equiv12\left(mod15\right)\)
Vậy A chia cho 15 dư 12
A = (tự chép lại đề)
\(\Leftrightarrow A=\left(330+1\right)^{332}+\left(333-1\right)^{333}+\left(332+1\right)^{334}\)
\(\Leftrightarrow A=\left(330+1+333-1+332+1\right)+\left(x\right)^{332+333+334}\)
\(\Rightarrow A=996\)
\(\Rightarrow A\)chia 15 dư : \(996:15=66\) dư 6
=> A chia 15 dư 6
A=(300 +1)^332 + (333-1)^333 +3^334.11^334
A=331^332-1^332 + 332^333 +1^333 +333^334
A=330(330^331 +330^330+...+1) +333(333^332 -333^331 +...-1) +333^334 chia het cho 3
A=331^332-1^332 +332^333 -2^333 + 333^334 +2^334 +2^333 -2.2^333 +1
A=330(330^331+...+1)+ 330(332^331 +...+2^331) +335 (333^333 -335^332.2+......-2^333) -2.(1+2^332) +3
A=..... -2(5(4^167 -4^156 +....-1)) +3
=> A chia 5 du 3
1 ) Ta có : \(2^{332}< 2^{333}=\left(2^3\right)^{111}=8^{111}\)
\(2^{223}>3^{222}=\left(3^2\right)^{111}=9^{111}\)
Vì : \(8^{111}< 9^{111}\)
\(\Rightarrow2^{332}< 3^{223}\)
2 ) Ta có : \(\left(222^3\right)^{111}=\left(2.111\right)^3=8.111^3\)
\(3^{222}=\left(333^2\right)^{111}=\left(3.111\right)^2=9.111^2\)
Vì : \(8.111^2< 9.111^2\)
\(\Leftrightarrow2^{333}< 3^{222}\)
1. Ta có:
\(2^{332}< 2^{333}=\left(2^3\right)^{111}=8^{111}\)
\(3^{223}>3^{222}=\left(3^2\right)^{111}=9^{111}\)
Vì \(8^{111}< 9^{111}\) nên \(2^{332}< 8^{111}< 9^{111}< 3^{223}\Rightarrow2^{332}< 3^{223}\)
Vậy \(2^{332}< 3^{223}\)
2. Ta có:
\(2^{333}=\left(2^3\right)^{111}=8^{111}\)
\(3^{222}=\left(3^2\right)^{111}=9^{111}\)
Vì \(8^{111}< 9^{111}\) nên \(2^{333}< 3^{222}\)
Vậy \(2^{333}< 3^{222}\)
a, Ta có : 222 ≡ 1(mod 13) nên 222^333 ≡ 1 (mod 13)
Và 333^2 ≡ -1 (mod 13) nên 333^222 ≡ -1 (mod 13)
Cộng lại ta có:
222^333 + 333^222 ≡ 0 (mod 13) đpcm
b, 2222 ≡ 3 (mod 7) ; 3³ ≡ -1 (mod 7) ; chú ý: 5555 = 3*1851 + 2
=> 2222^5555 ≡ 3^5555 ≡ (3³)^1851.3² ≡ (-1)^1851.9 ≡ -9 ≡ -2 ≡ 5 (mod 7)
5555 ≡ 4 (mod 7) ; 4³ ≡ 1 (mod 7) ; 2222 = 3*740 + 2
=> 5555^2222 ≡ 4^2222 ≡ (4³)^740.4² ≡ (1).16 ≡ 2 (mod 7)
vậy: 2222^5555 + 5555^2222 ≡ 5+2 ≡ 0 (mod 7) => đpcm
( tick đúng cho mink nha)