suku ke-5 dari barisan 256,128,64,.....

Bab Barisan dan Deret
Matematika SMP Kelas IX

256, 128, 64, ...
r = 128/256
r = 1/2

U5 = a x r⁴
U5 = 256 x (1/2)⁴
U5 = 256 x 1/16
U5 = 16

A = 256
R = 128/256 = ½

U5 :
= a x r^ⁿ-1
= 256 x ½^5-1
= 256 x ½^4
= 256 x 1/16
= 16