`G=1-5+5^{2}-5^{3}+5^{4}-...-5^{199}-5^{200}`
`5G=5-5^{2}+5^{3}-5^{4}+5^{5}-...-5^{200}-5^{201}`
`=>5G+G=1-2.5^{200}-5^{201}`
\(=>G=\dfrac{1-2.5^{200}-5^{201}}{6}\)
a, 1-2+3-4+5-6+....+2021-2022
b, 1-6+2-7+3-8+4-9+.......+35-40
c, -1+2-3+4-5+6-.........-2021+2022
d, 1-4+2-5+3-6+.....+197-200
e, -1-2-3-4-5-....-199-200
so sánh G= 1/2-3/4+5/6-...-199/200 và 1/51+1/52+1/53+...+1/100
TÍNH TỔNG:
a)A=3-3^2+3^3-3^4+...+3^99-3^100
b)B=-(4/5)+4/5^2-4/5^3+...-4/5^199+4/5^200
Cho T = 1 + 5 + 5^2 + 5^3 + ... +5^199
So sánh 4T với 5^200
1-2+3-4+5-6+...............+199-200
(-1)+2+(-3)+4+(-5)+6+...+(-199)+200
-1 - 2 -3 -3 -4 -5 -....- 199 - 200- 201-202
A = 1-2+3-4+5-6+...+199-200=
