nomor 28,33,34!! urgent dikumpul besokk

28) U1 = a = 84
U2 = a + b
80½ = 84 + b
b = 84 - 80½
b = 3½

33) a = 36
r = ⅓
Un = ar^n-1
4 = 36 . (⅓)^n-1
(⅓)^n-1 = 4/36
(⅓)^n-1 = 1/9
(⅓)^n-1 = (⅓)²
=> n - 1 = 2
=> n = 2 + 1
=> n = 3
jadi nilai 4 merupakan suku ke - 3

34) a = 1/32
r = 1/16 ÷ 1/32
r = 1/16 × 32/1
r = 2
U7 = ar^6
U7 = 1/32 • (2)^6
U7 = 1/32 • 64
U7 = 2