Question

Dik. suku ke 4 = 10/9 dan suku ke 6 = 10/81
ditanyakan??
a.rasio dan suku pertama
b. suku ke 10

Answer 1

U₆=U₄.r² => 10/81=10/9 . r² => 1/9 = r² => r=1/3
U₄=U₁.r³ => 10/9=U₁.(1/3)³ => 10/9=U₁.1/27 => U₁=30
U₁₀=U₆.r⁴ => 10/81 . (1/3)₄ = 10/6561

Answer 2

U4= a.r^3 = 10/9
u6= a.r^5 = 10/81
r^2= 9
r= 3

a.3^3 = 10/9
a.27 = 10/9
a= 1/30