A=2+5+9+14+...+19600+19998
Tính nhanh
A=6+16+30+48+...+19600+19998
B=2+5+9+14+...+4949+5049
C=1.2.3+2.3.4+3.4.5+...+98.99.100
A=6+16+30+48+...+19600+19998
2A = 1.3+2.4+3.5+...+99.101
B=2+5+9+14+...+4949+5049
2A = 1.4+2.5+3.6+...+99.102
C=1.2.3+2.3.4+3.4.5+...+98.99.100
4A = 1.2.3.4+2.3.4(5-1)+3.4.5.(6-2)+...+98.99.100.(101-97)
4A = 1.2.3.4+2.3.4.5-1.2.3.4+3.4.5.6-2.3.4.5+...+98.99.100.101-97.98.99.100
4A = 98.99.100.101
A=6+16+30+48+...+19600+19998
A : 2 = 3 + 8 + 15 + 24 + . . . + 9800 + 9999
A : 2 = 1.3 + 2.4 + 3.5 + 4.6 + . . . + 98.100 + 99.101
A : 2 = 1.[1+2] + 2.[1+3] + 3.[1+4] + 4.[1+5] + . . . + 98.[1+99] + 99.[1+100]
A : 2 = 1 + 1.2 + 2 + 2.3 + 3 + 3.4 + 4 + 4.5 + . . . + 98 + 98.99 + 99 + 99.100
A : 2 = 1 + 2 + 3 + 4 + . . . + 199 + 1.2 + 2.3 + 3.4 + 4.5 + . . . + 98.99 + 99.100
A : 2 = 4950 + 333300
A = 676500
Tính :
A = 4 + 12 + 24 + 40 + .......+ 19404 + 19800
B = 1 + 3 + 6 + 10 + .......... + 4851 +4950
C = 6 + 16 + 30 + 48 + ........... + 19600 + 19998
D = 2 + 5 + 9 + 14 + ............+ 4949 + 5044
F=1.3+2.4+3.5+...+2013.2015
J=6+16+30+...+19600+19998
K=2+5+9+14+...+4949+5049
Tính Tổng Của Từng Kết Qủa
A=6+16+30+48+...+19600+19998
tinh A=6+16+30+48+...19600+19998
6+16+30+48+...+19600+19998
6+16+30+48+....+19600+19998
D= 6+16+30+48+....+19600+19998
Tính s = 6 + 16 + 30 +48 + ... +19600 +19998