T=1.100+2.(100-1)+3.(100-2)+............+100.(100-99)
=(1.100+2.100+3.100+...........+100.100)-(1.2+2.3+3.4+............+99.100)
=99(1+2+3+..........+99)-333300
=99.\(\frac{99.\left(99+1\right)}{2}\)-333300
=490050-33330
=156750
Tính nhanh 1.100+2.99+3.98+...+99.2+100.1
Tính nhanh F = 1.100 + 2.99 + 3.98 + ... + 98.3 + 99.2 + 100.1
tính tổng B=\(1^2+2^2+3^2+....+99^2+100^2\)
tính tổng C=\(101^2+102^2+103^2+....+199^2+200^2\)
tính tổngT=1.100+2.99+3.98+....+99.2+100.1
Tính nhanh
A)A=1.2+2.3+3.4+....+98.3+99.2+100.1
B)B=1.100+2.99+3.98+...+98.3+99.2+100.1
Tính tổng:
F = 1.100 + 2.99 + 3.98 +...+ 98.3 + 99.2 + 100.1
F=1.100+2.99+3.98+...+99.2+100.1
Tính nhanh 1.100+2.99+3.98+...+98.3+99.2+100.1/1.2+2.3+3.4+...+99.100
tính nhanh . giúp mình nhanh nhek
A= 1.100+2.99+3.98+..+98.3+99.2+100.1
tinh tong
T=1.100+2.99+3.98+...+99.2+.100.1
S=1.3+2.4+...+99.101+100.102