\(9993^{1999}=\left(3^4\right)^{499}.3^3=\left(.............6\right).27=......2\)
\(5557^{1997}=\left(5557^4\right)^{499}.5557=\left(.....1\right).5557=.......7\)
=>A=(........2)\(-\)(........7)=(......5) chia hết cho 5
=>A chia hết cho 5
\(9993^{1999}=\left(3^4\right)^{499}.3^3=\left(.............6\right).27=......2\)
\(5557^{1997}=\left(5557^4\right)^{499}.5557=\left(.....1\right).5557=.......7\)
=>A=(........2)\(-\)(........7)=(......5) chia hết cho 5
=>A chia hết cho 5
chứng minh rằng:9993^1999-5557^1995 chia hết cho 5
cho A = 9999931999 . 5555571997 chung minh rang a chia het cho 5
Ta co
A= 999993^1999 -555557^1997
Chung minh rang
A chia het cho 5
Tim chu so tan cung cua cac so sau :
a) 571999
931999
b) Cho : A= 9999931999-5555571997. Chung minh rang A chia het cho 5
cho A =9999931999-5555571997 chung minh a chia het cho 5
chung minh rang 3^9999 - 1^1997 chia het cho 5
chung minh rang: A=(1999+19992+19993+...+19991998) chia het cho 2000
hãy chứng tỏ 19931999 - 55571997 chia hết cho 5
Chunng minh rang :
a) 995 -984 +973 -962 chia het cho 2 va 5
b) 5n-1 chia het cho 4 voi moi so tu nhien n
c) 88..8-9+n chia het cho 9( co n chu so 8)
d) 9999931999 _ 5555571997 chia het cho 5