Question

Barisan dan Deret Kelas XI

Answer 1

Verified answer

Bab Barisan dan Deret
Matematika SMA Kelas X

Pada suku ganjil, yaitu suku 1, 3, 5, 7, 9
r = 4/16
  = 1/4

Sn = (a . (1 - rⁿ)) / (1 - r)
  
S5 = (16 . (1 - (1/4)⁵) / (1 - (1/4))
     = (16 . (1.024/1.024 - 1/1.024)) / (4/4 - 1/4)
     = (16 . (1.023/1.024)) . 4/3
     = 341/16

Pada suku genap, yaitu suku 2, 4, 6, 8, 10

r = (-2) : (-8)
  = 1/4

Sn = (a . (1 - rⁿ)) / (1 - r)
  
S5 = ((-8) . (1 - (1/4)⁵) / (1 - (1/4))
     = ((-8) . (1.024/1.024 - 1/1.024)) / (4/4 - 1/4)
     = ((-8) . (1.023/1.024)) . 4/3
     = -341/32

S10 = S5 ganjil + S5 genap
       = 341/16 + (-341)/32
       = 682/32 - 341/32
       = 341/32