Question

Dada a P.G (9/8 , 3/4 , 1/2 ,...), calcule:
a)O oitavo termo:
b)O decimo quinto termo:

Answer 1

Resposta:

PG(9/8,3/4,1/2...)

q= 3/4/9/8

q= 3/4*8/9

q= 24/36

q= 2/3

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a8= 9/8*(2/3)^8-1

a8= 9/8*(2/3)^7

a8= 9/8*128/2187

a8= 16/243

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b) a15= 9/8*(2/3)^15-1

a15= 9/8* (2/3)^14

a15= 9/8* (16384/4782969)

a15= 2048/531441