Các câu hỏi tương tự
Cho biểu thức:
A = \(\frac{1}{21}+\frac{1}{22}+\frac{1}{23}+\frac{1}{24}+...+\frac{1}{40}\)
Hãy chứng tỏ \(\frac{1}{2}\) < A < 1
\(A=\frac{1}{21}+\frac{1}{22}+\frac{1}{23}+\frac{1}{24}+...+\frac{1}{40}\)
Câu 5.
Cho biểu thức A = \(\frac{1}{21}+\frac{1}{22}+\frac{1}{23}+...+\frac{1}{40}.\)
Chứng tỏ : \(\frac{1}{2}\) < A < 1
cho A =\(\frac{1}{22}+\frac{1}{23}+\frac{1}{24}+.......+\frac{1}{40}\)cmr \(\frac{1}{2}\)<A<1
Chứng minh:
\(\frac{7}{12}<\frac{1}{21}+\frac{1}{22}+\frac{1}{23}+...+\frac{1}{40}<\frac{5}{6}\)
\(S=\frac{1}{21}+\frac{1}{22}+\frac{1}{23}+\frac{1}{24}+\frac{1}{25}+\frac{1}{26}+\frac{1}{27}+\frac{1}{28}+\frac{1}{29}+\frac{1}{30}\)\(\frac{1}{30}\)
Hãy so sánh S với \(\frac{1}{3}\)
Cho \(A=\frac{1}{21}+\frac{1}{22}+\frac{1}{23}+...+\frac{1}{100}\)Chứng mainh:\(1< A< \frac{7}{3}\)
\(Cho\)\(A=\frac{1}{21}+\frac{1}{22}+\frac{1}{23}+...+\frac{1}{100}\). Chứng minh \(1< A< \frac{7}{3}\)
a,\(\frac{1995\cdot1994-1}{1994+1996\cdot1995}\)b,\(\frac{864\cdot48-432\cdot96}{864\cdot48\cdot432}\)c,\(\frac{1414+1515+1616+1717+1818+1919}{20\cdot20+21\cdot21+22\cdot22+23\cdot23+24\cdot24+25\cdot25}\)
d,\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+\frac{1}{15}+\frac{1}{21}+...+\frac{1}{3240}\)