Question

Calcule o nono termo da PG (5,10,20, ...

Answer 1

An = a1.q^(n-1)

A9 = 5.2^(9-1)

A9 = 5.2^8

A9 = 5. 256

A9 = 1 280                  ok

Answer 2

an=a1.q^n-1
a9=5 . 2^9-1
a9= 5 . 2^8
a9= 5. 256
a9=1280