+ 

Ta có : 

\(0,0\left(8\right)=\frac{4}{45}\)

\(0,1\left(2\right)=\frac{11}{90}\)

\(0,1\left(23\right)=\frac{61}{495}\)

Ta có:

\(0,0\left(8\right)=0,0\left(1\right).8=\frac{0,\left(1\right)}{10}.8=\frac{1}{90}.8=\frac{8}{90}\)

Tương tự hết!

\(0,1\left(2\right)=0,1+0,0\left(2\right)=\frac{1}{10}+\frac{\frac{2}{9}}{10}=\frac{1}{10}+\frac{1}{45}=\frac{11}{90}\)

0,0(8) = \(\frac{1}{10}\).0,(8) = \(\frac{1}{10}.\frac{8}{9}=\frac{4}{45}\)

0,1(2) = (12-1)/ 90= 11/90

0,1(23) = (123-1)/990 = 122/990 

làm là phải đúng, sai thì k làm, hại bn mk sao

\(0,1\left(23\right)=1\times\frac{0,\left(23\right)}{10}=1\times\frac{23\times0,\left(01\right)}{10}=1\times\frac{23\times\frac{1}{99}}{10}=\frac{23}{990}\)

\(\frac{61}{495}\)

\(0,1\left(23\right)=\dfrac{61}{495}\\ 0,1\left(2\right)=\dfrac{11}{90}\)

\(\dfrac{61}{495}\);\(\dfrac{11}{90}\)

0,1(23)=1(23)/10(0)
0,1(2)= 1(2)/10(0)
 

0,1(2)=\(\frac{12-1}{90}=\frac{11}{90}\)

0,1(23)=\(=\frac{123-1}{990}=\frac{122}{990}=\frac{61}{495}\)