Question

determine o nôno termo da P.G (1/81 ;1/27 ;1/9)

Answer 1

q= a2/a1
q= 1/27 : 1/81
q= 1/27 . 81/1
q= 81/27
q= 3

a9=a1.q^8
a9= 1/81 . 3^8
a9= 3^8 /3^4
a9 = 3^4
a9 = 81