Chứng minh rằng \(\frac{1}{5}+\frac{1}{15}+\frac{1}{25}+...+\frac{1}{1985}< \frac{9}{20}\)
Chứng minh rằng:
\(\frac{1}{5}+\frac{1}{15}+\frac{1}{25}+..........+\frac{1}{1985}< \frac{9}{20}\)
Chứng minh: \(\frac{1}{5}+\frac{1}{15}+\frac{1}{25}+...+\frac{1}{1985}<\frac{9}{20}\)
Chứng minh rằng : \(\frac{1}{5}+\frac{1}{15}+\frac{1}{25}+...+\frac{1}{1985}<\frac{9}{20}\)
Chứng minh rằng:\(\frac{1}{5}+\frac{1}{15}+\frac{1}{25}+...+\frac{1}{1985}< \frac{9}{20}\)
Giúp mik va ạ!
CMR \(A=\frac{1}{5}+\frac{1}{15}+\frac{1}{25}+...+\frac{1}{1985}< \frac{9}{20}\)
Chứng minh: \(\frac{1}{5}\)+\(\frac{1}{15}\)+\(\frac{1}{25}\)+ .........+\(\frac{1}{1985}\)<\(\frac{9}{20}\)
CMR:\(\frac{1}{5}+\frac{1}{15}+\frac{1}{25}+...+\frac{1}{1985}< \frac{9}{20}\)
CMR:
\(\frac{1}{5}+\frac{1}{15}+\frac{1}{25}+...+\frac{1}{1985}< \frac{9}{20}\)