\(5^{10}.9+5^9.8\)
\(=5^9.5.9+5^9.8\)
\(=5^9.\left(45+8\right)\)
\(=5^9.53\)
còn lại thì mình ko biết
\(5^{10}.9+5^9.8\)
\(=5^9.5.9+5^9.8\)
\(=5^9.\left(45+8\right)\)
\(=5^9.53\)
còn lại thì mình ko biết
bai 1 ;chung minh rang abcd chia het 99 thi ab cong cd chia het 99 va nguoc lai
bai 2;a.8 mu 10 tru 8 mu 9 tru 8 mu 8 chia het 55
b.7mu 6 cong 7 mu 5 tru 7 mu 4 chia het 11
d.10 mu 9 cong10 mu 8 cong 10 mu 7 chia het 555
c.81mu 7 cong 27 mu 9 tru 9 mu 13 chia het 45
1) chung to rang
a) 76 + 75 - 74 chia het cho 11
b )278 - 321 chia het cho 26
c) 812 - 2 33 - 230 chia het cho 55
2) tim chu so tan cung cua tong
30 mu 4 mu 1 mu 9 mu 9 mu 9 + 15 mu 5 mu 1 mu 9 mu 9 mu 9
3 mu 3 nhan 9 tru 3 mu 4 nhan 3 cong 5 mu 8 nhan 5 mu 0 tru 5 mu 12 chia 25 mu 2
8 mu 10 - 8 mu 9 -8 mu 8 /55
B=1/3+1/3 mu 3 +1/3 mu 5 +1/3 mu 7 + ...+1/3 mu 99
M= 3/1 mu 2 . 2 mu 2 +5/2 mu 2 . 3 mu 2+7/3 mu 2 . 4 mu 2 + ...+19= 9 mu 2 . 10 mu 2
a] 4 mu 2016: 4 mu 2015 + 10.10 mu 2 =
b] 3 mu 4 . 47 . 63 - 3 mu 4 . 10 =
c] 2016 : { 2464 : [171 - 5 ( 9 mu 2 - 7 mu 2)]} =
d] 1 + 3+ 5 +....... + 2011 + 2013=
(1 + 5 mu 2 + 5 mu 4 + 5 mu 6 + 5 mu 8)*x = 5 + 5 mu 2 + 5 mu 3 + 5 mu 4 +....+ 5 mu 10
khong tinh gia tri bieu thuc hay so sanh 9 mu 8 nhan 5 mu 16 va 19 mu 20
bai 1; cho tong M =126 +213+x. Tim x de M chia het cho 3
bai 2; chung to rang tong ; A= 2 + 2 mu 3 + 2 mu 4 + 2 mu 5 + 2 mu 6 +2 mu 7 +2 mu 9 + 2 mu 10 + 2 mu 12 chia het cho 5