Các câu hỏi tương tự
chứng minh rằng \(\frac{1}{65}\)<\(\frac{1}{5^3}+\frac{1}{6^3}+...+\frac{1}{2004^3}\)<\(\frac{1}{40}\)
chứng minh rằng
\(\frac{1}{5^3}+\frac{1}{6^3}+\frac{1}{7^3}+...+\frac{1}{2004^3}\)<\(\frac{1}{40}\)
chung minh : 1/5^3+1/6^3+1/7^3+........+1/2004^3 <1/40
chung minh rang 1/5^3+1/6^3+1/7^3+..........+1/2004^3<1/40
chung minh : 1/5^3+1/6^3+1/7^3+.........+1/2004^3 < 1/40
chứng minh rằng:1/5^3+1/6^3+1/7^3+....+1/2013^3<1/40
Chứng minh rằng \(\frac{1}{5^3}+\frac{1}{6^3}+\frac{1}{7^3}+....+\frac{1}{2013^3}<\frac{1}{40}\)
a)B=1/3+1/3^2+1/3^3+...+1/3^2004+1/3^2005. chứng minh rằng B<1/2
b)B=2+22+33+34+35+...+32010. chứng minh B chia hết cho 7
chứng minh rằng:1/5^3+1/6^3+....+1/2013^3<1/40