Các câu hỏi tương tự
Tính tổng sau bằng phương pháp khử liên tiếp :
\(a,P=\frac{1}{2}+\frac{1}{2^3}+\frac{1}{2^5}+...+\frac{1}{2^{2019}}\)
1/tính nhanh
a/\(A=\frac{7}{8}:\left(\frac{2}{9}-\frac{1}{18}\right)+\frac{7}{8}:\left(\frac{1}{36}-\frac{5}{12}\right)\)
b/\(B=\frac{1+0,6-\frac{3}{7}}{\frac{8}{3}+\frac{8}{5}-\frac{8}{7}}-\frac{\frac{1}{3}+0,25-\frac{1}{5}+0,125}{\frac{7}{6}+\frac{7}{8}-0,7+\frac{7}{16}}\)
Tính: \(\frac{1}{18}+\frac{1}{36}+.....+\frac{1}{29700}\)
Tính nhanh
1, \(10\frac{5}{4}-4\frac{9}{14}-6\frac{5}{7}+\frac{7}{3}\)
2, \(\frac{29}{32}\left(\frac{41}{36}-\frac{32}{58}\right)-\frac{41}{36}\left(\frac{29}{32}+\frac{18}{41}\right)\)
Tính :
M = \(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+...+\frac{1}{4970}\)
N = \(\frac{1}{18}+\frac{1}{54}+\frac{1}{108}+...+\frac{1}{990}\)
P = \(\frac{1}{90}-\frac{1}{72}-\frac{1}{56}-...-\frac{1}{6}-\frac{1}{2}\)
\(\text{Tính tổng }A=\frac{1}{2}+\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+\frac{1}{15}+...+\frac{1}{36}+\frac{1}{45}\)
Tính nhanh E=\(\frac{6}{8+1}.\frac{6}{18+1}.\frac{6}{30+1}...\frac{6}{10700+1}\)
tính nhanh
\(\frac{7}{8}:\left(\frac{2}{9}-\frac{1}{18}\right)+\frac{7}{8}:\left(\frac{1}{36}-\frac{5}{12}\right)\)
Tính hợp lý:
\(\frac{16}{9}-\frac{1}{36}-\frac{1}{28}-\frac{1}{21}-\frac{1}{15}-\frac{1}{10}-\frac{1}{6}-\frac{1}{3}-1\)