Respostas

2014-04-27T10:26:38-03:00
A formula de PG é a_{n} =a_{1} x q^{n-1}
 a_{4} = 12
q= 2
 a_{8} =?
Aplicando....

a_{n} = a_{1} x q^{n-1}
a_{4} =a_{1} x 2^{4-1}
12=a_{1} x 2^{3}
12=a_{1} x8
 \frac{12}{8} =a_{1}
1,5=a_{1}

a_{8} =1,5x 2^{8-1}
a_{8} =1,5x 2^{7}
a_{8} =1,5x128
a_{8} =1024


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