a) đây chỉ là 1 trong nhiều cách
\(\frac{7}{8}=\frac{1}{8}+\frac{4}{8}+\frac{2}{8}\)
a) \(\frac{7}{8}=\frac{1}{2}+\frac{1}{4}+\frac{1}{8}\)
b) \(\left(1-\frac{1}{2}\right).\left(1-\frac{1}{3}\right).\left(1-\frac{1}{4}\right).\left(1-\frac{1}{5}\right)\)
\(=\frac{1}{2}.\frac{2}{3}.\frac{3}{4}.\frac{4}{5}\)
\(=\frac{1.2.3.4.}{2.3.4.5}\)
\(=\frac{1}{5}\)
( Dấu chấm là dấu nhân nha bạn )
\(a;\)
\(\frac{7}{8}=\frac{1}{8}+\frac{2}{8}+\frac{4}{8}\)
\(\Rightarrow\frac{7}{8}=\frac{1}{8}+\frac{1}{4}+\frac{1}{2}\)
\(b;\)
\(\left(1-\frac{1}{2}\right)\times\cdot\cdot\cdot\times\left(1-\frac{1}{5}\right)\)
\(=\frac{1}{2}\times\cdot\cdot\cdot\times\frac{4}{5}\)
\(=\frac{1}{5}\)