6/21; 7/21; 8/21; 9/21; 10/21; 11/21; 12/21; 13/21; 14/21; 15/21; 16/21
1/21 ; 2/21 ; 3/21 ; 4/21 ; 5/21 ; … ; 17/21 ; 18/21 ; 19/21 ; 20/21
1/21+2/21+3/21+4/21+5/21+…+17/21+18/21+19/21+20/21
a,9/4-[-11}/-4
b, 7/8-3/-8-1/8
c,-5/21-25/21-[-1]/21
d, 18/24-35/-10
e, 3/7-11/14-19/28
g, 5/-{-2}/3-1/12
h, 3/17-{-5}/13-{-18}/35-14/17-17/{-35}-{-8}/13
120 - { 17^18 : 17^17 + 2^2 [3 ( 21^27 : 21^20 - 5 . 3^3 )]}
Giúp với ạ, không biết giải T_T
bài 3: Tính:
1) 1/6 - -5/6 2) 6/13 - -14/39 3) 4/5 - 4/-18 4) 7/21 - 9/-36
5) -12/18 - -21/35 6) -3/21 - 6/42 7) -18/24 - 15/21 8) 1/6 - 2/5
các bn giup mik mik vs
13^20= 120^21=
14^20=
15^20=
16^20=
17^20=
18^20=
19^20=
20^20=
21^20=
22^20=
121^21=
122^21=
123^21=
124^21=
125^21=
126^21=
127^21=
128^21=
129^21=
23^27=
24^27=
25^27=
26^27=
27^27=
28^27=
29^27=
30^27=
31^27=
32^27=
Tính 21-20+19+18-17-16+15+14-13-12+10+9-8-7+...-5-4+3+2-1
8/19 + 4/21 - 53 3/53 + 17/21 - 27/19
75/100+18/21+19/32+1/4+3/21+13/23
