Respostas

2013-07-17T12:09:30-03:00
a4=a1*q³
1/1250=4*q³
1/1250/4=q³
1/1000=q³
q=³√1/1000
q=1/10
2013-07-17T12:49:17-03:00
A4 = a1 + 3r
1/250 = 4 + 3r
3r = 1/250 - 4
750r = 1 - 1000
750r = 999
r = 999/750
r = 333/250

a2 = a1 + r
a2 = 4 + 333/250
a2 = (1000 + 333)/250
a2 = 1333/250