12 - 1 = 11 13 - 1 = 12 14 - 1 = 13
17 - 5 = 12 18 - 2 = 16 19 - 8 = 11
14 - 0 = 14 16 - 0 = 16 18 - 0 = 18
12 - 1 = 11 13 - 1 = 12 14 - 1 = 13
17 - 5 = 12 18 - 2 = 16 19 - 8 = 11
14 - 0 = 14 16 - 0 = 16 18 - 0 = 18
(-10)+(-9)+(-8)+...+0+1+2+3+...+10+11+12+13+14+15+16+17+18+19+20
Bài 13: Dấu <, =, >
10 … 10 + 3
11 + 2…. 2 + 11
9 … 10 + 9
10 … 10 + 0
17 – 4 … 14 - 3
18 – 4 … 12
15 … 15 – 1
17 + 1… 17 + 2
12+ 5 … 16
16 … 19 - 3
15 – 4 … 10 + 1
19 – 3 … 11
tính 1*2*3*4*5*6*7*8*9*10*11*12*13*14*15*16*17*18*19*0*20*21*22*23*24*25*26*27*28*29*30*31*32
ai nhanh mình tích cho
Tính nhẩm:
15 - 5 = 11 - 1 = 16 - 3 =
12 - 2 = 18 - 8 = 14 - 4 =
13 - 2 = 17 - 4 = 19 - 9 =
Tính:1-2+3-4+5-6+7-8+9-10+11-12+13-14+15-16+17-18+19-20+21
tính thuận tiện : 1+2+3+4+5+6+7+8+9+10+11+12+13 +14 +15+16+17+18+19
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19
1+1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20=may
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20=