Question

[Lê Thái Thảo Nghi]

tính (1-2/6).(1-2/12).(1-2/20)...(1-2/9900)

Answer 1

[soyeon_Tiểu bàng giải]

\(\left(1-\frac{2}{6}\right)\left(1-\frac{2}{12}\right)...\left(1-\frac{2}{9900}\right)\)

\(=\frac{4}{6}.\frac{10}{12}...\frac{9898}{9900}\)

\(=\frac{1.4}{2.3}.\frac{2.5}{3.4}...\frac{98.101}{99.100}\)

\(=\frac{1.2...98}{3.4...100}.\frac{4.5...101}{2.3...99}\)

\(=\frac{2}{99.100}.\frac{100.101}{2.3}\)

\(=\frac{101}{99.3}\)

\(=\frac{101}{297}\)

Answer 2

[cure happy]

đáp số:\(\frac{101}{297}\)

ai k mk mk sẽ k lại ^-^