\(\frac{81}{9}\)
\(=\)\(\frac{9}{1}\)
\(=9\)
\(\frac{81}{9}\)
\(=\)\(\frac{9}{1}\)
\(=9\)
So sánh hai phân số:
\(\frac{6}{5}and\frac{5}{6}\);\(\frac{8}{9}and\frac{21}{81}\);\(\frac{9}{63}and\frac{90}{7}\);\(\frac{8}{81}and\frac{10}{9}\)
\(\frac{2}{3}+\frac{2}{9}+\frac{2}{27}+\frac{2}{81}+\frac{2}{243}=\)
\(\frac{2}{9}\)+\(\frac{-2}{9}\)x\(\frac{2}{9}\): \(\frac{14}{81}\)
\(A=1+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+\frac{1}{81}\)
Tìm A,biết:
A = \(\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+\frac{1}{81}+.........+\frac{1}{6561}\)
Tính nhanh tổng sau \(1+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+\frac{1}{81}+\frac{1}{243}+\frac{1}{729}\)
Tính nhanh:
\(1+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+\frac{1}{81}+\frac{1}{243}+\frac{1}{729}\)
Giúp mk nha!
Tính giá trị biểu thức
\(\frac{1}{10}+\frac{2}{20}+\frac{9}{30}+\frac{16}{40}+\frac{25}{50}+\frac{36}{60}+\frac{49}{70}+\frac{69}{80}+\frac{81}{90}\)
Tìm biết: