Xét vế trái: 1-1/2+1/3-1/4+1/5-1/6+...+1/199-1/200
=(1+1/3+1/5+..+1/199)-(1/2+1/4+..+1/200)
=(1+1/2+1/3+1/4+1/5+...+1/199+1/200)-2.(1/2+1/4+..+1/200)
=1+1/2+1/3+1/4+1/5+..+1/199+1/200-1-1/2-...-1/100
=1/101+1/102+1/103+...1/200
Vậy vế trái bằng vế phải
Chứng minh rằng:
1 - 1/2 + 1/3 -1/4 + ... + 1/199 - 200= 1/101 + +1/102 + 1/103 + ... + 1/200
chứng minh rằng :1-1/2+1/3-1/4+...+1/199-1/200 = 1/101+1/102+1/103+1/104+...+1/200.
chứng minh rằng: 1-1/2+1/3-1/4+.......+1/199-1/200=1/101+1/102+1/103+.......+1/200
hãy chứng tỏ rằng:1-1/2+1/3-1/4+......+1/199-1/200=1/101+1/102+1/103+.....+1/200
chứng tỏ 1/101+1/102+1/103+.........+1/200=1-1/2+1/3-1/4+.........+1/199-1/200
1-1/2+1/3+1/4+...+1/199+1/200=1/101+1/102+1/103+...+1/200
CMR:1/101+1/102+1/103+...+1/200=1-1/2+1/3-1/4+...+1/199-1/200
CMR: 1-1/2+1/3-1/4+...+1/199-1/200=1/101+1/102+1/103+...+1/200
Chứng minh
1/101+1/102+1/103+...+1/199+1/200 bé hơn 1
