Ta có: \(A=\frac{1}{101}+\frac{1}{102}+\frac{1}{103}+...+\frac{1}{299}+\frac{1}{300}>\frac{1}{300}.200=\frac{2}{3}\Rightarrow A>\frac{2}{3}\Rightarrowđpcm\)
Chứng minh:
1/101+1/102+1/103+...+1/299+1/300>2/3
tính A:B bt A=1/1*300+1/2*301+...+101*400
B=1/1*102+11/2*103+...+1/299*400
tính A/B biết :
A=1/1*300+1/2*301+1/3*302+...+1/101*400
B=1/1*102+1/2*103+1/3*104+...+1/299*400
Tính A/B biết rằng:
A=1/1*300 + 1/2*301 + 1/3*302 + ... + 1/101*400
B=1/1*102 + 1/2*103 + 1/3*104 + ... + 1/299*400
tính A/B biết:
A=1/1*300+1/2*301+....+1/101*400
B=1/1*102+1/2*103+...+1/299*400
CMR:
\(\frac{1}{101}+\frac{1}{102}+\frac{1}{103}+...+\frac{1}{299}+\frac{1}{300}>\frac{2}{3}\)\(\frac{2}{3}\)
1/101+1/102+.....+1/299+1/300>2/3
Chứng tỏ rằng 1/101+1/102+....+1/299+1/300>2/3
chung to rang 1/101+1/102+...+1/299+1/300>2/3