Các câu hỏi tương tự
bai 4 , tinh gia tri bieu thuc ;
a,A=2 mu 1 + 2 mu 2 +2 mu 3 +......+2 mu 2019
b, B=1+3+3 mu 2 +3 mu 3 +......+3 mu 2020
khong tinh gia tri bieu thuc hay so sanh 9 mu 8 nhan 5 mu 16 va 19 mu 20
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
cho 4 mu x . 9 mu y=6 mu 4 va81 mu x : 9 mu 2y=1 (voi x,y e N) . Hay tinh gia tri cua A=x mu 18+y mu 12 + 2014
8 mu 2 chia 9 cong 50 chia 2 tru ba mu ba nhan 3 mu 0
(tinh nhanh neu co the)
Viet Ket qua phep tinh duoi dang mot luy thua :
a) 23 .22.2.4
B) 10 mu 2 .10 mu 3 .10 mu 5
C) X.X mu 5
D) A mu 3 .a mu 2 .a mu 5
Tinh nhanh cac gia tri cua bieu thuc
[ ( 2 mu 5:2-2 mu 2×2 mu 2)×9999]+10000
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
B1) Tinh
a) 245-4 . [15: 8 +2.(4+3 mu 2 -9)]
b) 375: 5 mu 3 -( 3 mu 8: 3 mu 6 -2 .2 mu 3)
B2: Tim x
a) 2x -2 mu 3 .3 mu 2=138
b) ( 6x- 3 mu 4) . 7 mu 3= 3 . 7 mu 4
c) 1+2+3+..............+x =500500