Respostas

2014-05-10T12:17:45-03:00
X=0,9999...
10x=9,999...
10x-x=9
9x=9
X=9/9
X=1
2014-05-10T12:23:08-03:00
A)7/4
b)-4/25
c)6/5
d)3125/990