pada barisan 4,2,1,(1/2) tentukan suku k 10

-2,-4,-6,-8,-10,-12,-14

a= 4
r = 2/4 = 1/2

[tex]u10 = a {r}^{10 - 1} \\ u10 = 4 \times \frac{1}{2} ^{9} \\ u10 = 4 \times \frac{1}{512} = \frac{1}{128} [/tex]