Question

Quantos termos tem a PG ( 4, 8, 16, ... 2 048)
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Answer 1

an = a1.q^(n-1)

2048 = 4.q^(n-1)

q = 8/4 = 2

2048 = 4.2^(n-1)

512 = 2^(n-1)

512 = 2^9

2^9 = 2^(n-1)

9 = n-1

n = 10