+0  
 
0
1301
3
avatar+1310 

Find $1-0.\overline{9}.$

 May 25, 2015

Best Answer 

 #3
avatar+26376 
+15

Find $1-0.\overline{9}.$

 

$$\left
\begin{array}{rcl}
10 \times 0.\overline{9} &=& 9.\overline{9} \\
1 \times 0.\overline{9} &=& 0.\overline{9}
\end{array} \right\} -
\\
\hline$$

 

$$\begin{array}{rcl}
(10-1)\times 0.\overline{9} &=& 9.\overline{9} - 0.\overline{9} \\
9 \times 0.\overline{9} &=& 9 \\
9 \times 0.\overline{9} &=& 9 \qquad | \qquad : 9 \\
0.\overline{9} &=& \dfrac{9}{9} \\
0.\overline{9} &=& 1 \\
\end{array}$$

 

 

$1-0.\overline{9}.$ = 1 - 1 = 0

 May 26, 2015
 #1
avatar+128731 
+10

Note that........

                                                                      

(1.00000....) - (.9999......)   = .(00000).....1  = .01    where the "bar" is over the "0'

 

{sorry.....I dont know how to insert the bar  !!!}

 

 

 

 

 

 May 25, 2015
 #2
avatar+118613 
+15

$$\\0.\bar3=\frac{1}{3}\\\\
3*0.\bar3=3*\frac{1}{3}\\\\
therefore\\
0.\bar9=1\\\\\\
1-0.\bar9 = 1-1 = 0$$

.
 May 26, 2015
 #3
avatar+26376 
+15
Best Answer

Find $1-0.\overline{9}.$

 

$$\left
\begin{array}{rcl}
10 \times 0.\overline{9} &=& 9.\overline{9} \\
1 \times 0.\overline{9} &=& 0.\overline{9}
\end{array} \right\} -
\\
\hline$$

 

$$\begin{array}{rcl}
(10-1)\times 0.\overline{9} &=& 9.\overline{9} - 0.\overline{9} \\
9 \times 0.\overline{9} &=& 9 \\
9 \times 0.\overline{9} &=& 9 \qquad | \qquad : 9 \\
0.\overline{9} &=& \dfrac{9}{9} \\
0.\overline{9} &=& 1 \\
\end{array}$$

 

 

$1-0.\overline{9}.$ = 1 - 1 = 0

heureka May 26, 2015

2 Online Users

avatar
avatar