\(\left(1-\frac{2}{6}\right)\left(1-\frac{2}{12}\right)...\left(1-\frac{2}{9900}\right)\)
\(=\frac{4}{6}.\frac{10}{12}...\frac{9898}{9900}\)
\(=\frac{1.4}{2.3}.\frac{2.5}{3.4}...\frac{98.101}{99.100}\)
\(=\frac{1.2...98}{3.4...100}.\frac{4.5...101}{2.3...99}\)
\(=\frac{2}{99.100}.\frac{100.101}{2.3}\)
\(=\frac{101}{99.3}\)
\(=\frac{101}{297}\)
đáp số:\(\frac{101}{297}\)
ai k mk mk sẽ k lại ^-^