Pada barisan geometri diketahui B. U3 = 64 dan U6 = 8 Tentukan U5??

Dik. barisan deret geometri : U3= 64 & U6 = 8.
Dit. U5?

Jawab...

U3 = a x r² =64
U6 = a x r⁵ = 8
     ------------------------- (:)
@ r³ = 1/8
@ r = 1/2

a : 
a x r² = 64
a x (1/2)² = 64
a x 1/4 = 64
a = 64 x 4/1
a = 256

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

Semoga membantu... ^_^