Respostas

2014-05-11T12:40:08-03:00
A) an=a1+(n-1).r
a8=28+(8-1).8
a8=28+7.8
a8=28+56=84

b)an=ai+(n-1).r
a19=28+(19-1).8
a19=28+18.8
a19=28+144=172
11 3 11
2014-05-11T12:49:24-03:00
A) oitavo termo a8=a1 +7r
a8= 28+7x8=
a8=28+56
a8=94

b)decimo nono termo
a19= a1+ 18r
a19=28 + 18x8
a19= 28+144
a19=174
3 2 3