(-7+6+2)+[-5+(-6)-98]=
(-1 + 2) + [-11 - 98]
= 1 - 109 = -108
(-7+6+2)+[-5+(-6)-98]
=(6+2-7)+[-5-6-98]
=1-5-6-98
=1-(5+6+98)
=1-108
=-107
Xin loi nhe minh nham mot chut
=1-109
=-108
(-7+6+2)+[-5+(-6)-98]=
(-1 + 2) + [-11 - 98]
= 1 - 109 = -108
(-7+6+2)+[-5+(-6)-98]
=(6+2-7)+[-5-6-98]
=1-5-6-98
=1-(5+6+98)
=1-108
=-107
Xin loi nhe minh nham mot chut
=1-109
=-108
A=1-2-3-4=5-6-7-8+9-10-11-12+...+97-98-99-100
B=1+2-3-4+5+6-7-8+....+97+98-99-100
1) 15 - 98 + 91 - 75 + 98 - 91 - 13
2) 5 - ( 4 - 7 + 12 ) + ( 4 - 7 + 12 ) - 10
3) 20 - ( 25 - 98 + 12 ) + ( 25 - 98 - 72 )
4) - ( 17 - 4 + 13 + | -17 | + 13 )
5) | -16 | - ( 5 - 8 + 7) - ( - 5 ) - 8
6) -20 + ( 3 - 16 + 7 ) - ( 3 - 16 + 7 )
7) 32 - ( 5 - 8 + 32 ) + ( 5 - 8 + 6 )
8) -20 - ( 25 - 11 + 8 ) + ( 25 - 8 + 20 )
Tính D=2*4+3*5+4*6+5*7+6*8+7*9+...+97*99+98*100
Tính tổng sau : A = 1 - 2 + 3 - 4 + 5 - 6 + 7 - 8 + ... + 99 - 100
B=1–2- 3+4+5-6-7+8+...+97-98-99+100
A = 1 . 3 + 3 . 5 + 5 . 7 + ... + 49 . 51
B = 2 . 4 + 4 . 6 + 6 . 8 + ... + 98 . 100
C = 1 . 4 + 4 . 7 + 7 . 10 + ... + 301 . 304
D = 1 . 2 . 3 + 2 . 3 . 4 + ... + 98 . 99 . 100
tính D=2*4+3*5+4*6+5*7+6*8+7*9+8*10+...+97*99+98*100
D = 1 - 6 + 11 - 16 + ... + 111
F = 2^100 - 2^99 - 2^98 - ...- 2^2 - 2 - 1
E = 1 + 2 - 3 -4 +5 + 6 - 7 - 8 +....+ 249 + 250
H = 1 -2 -3 -4 - 5 -6 - ... -97 - 98 - 99 - 100
Tính nhanh
a) 1 - 2 - 3 + 4 + 5 - 6 -7 + 8 + .... + 97 - 98 - 99 + 100
b) 1 - 6 + 11 - 16 + ... + 91 - 96
c) 2 - 5 + 8 - 11 + 14 - 17 +... + 98 - 101
1) 7. (3x+5)+2.(7x+14)=98. 2) 4. (x -5)+3.(x+7)=22
3) 5.(4-x) +7.(x-2)=24. 4) 3.(x -5)+6.(x+3)=12
5) 4-x+5.(x+2)=38. 6) 5.( x-3)+2.(x+8)=22
7) 5.(x-7)+10.(4+x)=20. 8) 4.(x+10)+8.(x-3)=24
9) 4.(5-x)+5.(x-2)=15. 10) 4.(x-1)+3.(x-2)=-1