\(\frac{1}{2}\cdot\frac{2}{3}\cdot\frac{3}{4}...\frac{2018}{2019}\)
\(=\frac{1\cdot2\cdot3\cdot4\cdot\cdot\cdot2018}{2\cdot3\cdot4\cdot5\cdot\cdot\cdot2019}\)
\(=\frac{1\cdot\left(2\cdot3\cdot4\cdot\cdot\cdot2018\right)}{\left(2\cdot4\cdot5\cdot\cdot\cdot2018\right)\cdot2019}\)
\(=\frac{1}{2019}\)
Vậy .......................................
1/2.2/3.3/4.....2018/2019
=1.2.3......2018/2.3.4......2019
=1/2019
\(\frac{1}{2}.\frac{2}{3}.\frac{3}{4}...\frac{2018}{2019}\)
\(=\frac{1.2.3...2018}{2.3.4...2019}\)
\(=\frac{1}{2019}\)
\(\frac{1}{2}.\frac{2}{3}.\frac{3}{4}....\frac{2018}{2019}=\frac{1}{2019}\)
Chúc hok tốt!!!
\(\frac{1}{2}.\frac{2}{3}.\frac{3}{4}.....\frac{2018}{2019}\)
\(=\frac{1.2.3.....2018}{2.3.4.5.....2019}\)
\(=\frac{1}{2019}\)
các bạn có thể trình bày cụ thể giúp mk đc ko
\(\frac{1}{2}.\frac{2}{3}.\frac{3}{4}....\frac{2018}{2019}\)
\(=\frac{1.2.3....2018}{2.3.4....2019}\)
\(=\frac{1}{2019}\)
