Tính tỉ số A/B biết:
A= 1/1*2+1/3*4+1/5*6+...+1/199+200
B= 1/101*200+1/102*199+...+1/200*101
Tính tỉ số A/B biết:
A= 1/1*2+1/3*4+1/5*6+...+1/199+200
B= 1/101*200+1/102*199+...+1/200*101
1-2+3-4+5-6+...............+199-200
A = 1-2+3-4+5-6+...+199-200=
A=1-2+3-4+5-6+...+199-200
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
A=1/2+3/4+5/6+........+199/200
chung to rang A^2<1/200
1-2+3-4+5-6+7-8+.............+199-200
d. 1 - 2 + 3 - 4 + 5 - 6+ ... + 199 - 200