Hitunglah 9+11+13+...+107

a =9
b =11-9 =2

Un = 107
a + (n-1)b =107
9 + 2n - 2 =107
2n =107 - 7
2n =100
n =50

Sn =n/2 (a +Un)
S50 = 50/2 (9 +107)
S50 =25 (116)
=2900

Mapel : Matematika
Materi : Barisan dan Deret
Kelas : 9


9, 11, 13,..., 107

a = 9
b = 11 - 9 = 2

⏩Tentukan banyak suku

Un = 107
a + (n - 1)b = 107
9 + (n - 1)(2) = 107
2n + 7 = 107
2n = 107 - 7
2n = 100
n = 100/2
n = 50

Maka, Jumlah Suku barisan

Sn = n/2 [a + Un]

S50 = 50/2 [9 + 107]

S50 = 25 x 116

S50 = 2.900 ✔