Diketahui barisan 5,8,11.... Suku ke 120 adalah...

Bab Barisan dan Deret

5,8,11,....

a = 5
b = 8 - 5 = 3

Un = a +(n-1) b
U120 = 5 + (120 - 1) 3
U120 = 5 + 119 × 3
U120 = 5 + 357
U120 = 362

U120 = a + (n - 1 )b
= 5 + (120- 1)3
= 5+ 119 × 3
= 5+ 357
= 362