rumus suku ke-n barisan bilangan 5,8,11,14,17

Materi : Barisan dan Deret
Bahasan : Barisan Aritmatika
Jawaban : Un = 3n + 2

Langkah - langkah :
5, 8, 11, 14, 17, x, memiliki :
a = 5
b = 8 - 5 = 3
Un = a + (n - 1)b

Un = 5 + (n - 1)3
Un = 5 + 3n - 3
Un = 3n + 2

Arithmetic Sequence.

5, 8, 11, 14, 17, ...
a = U₁ = 5
b = U₂ - U₁ = 8 - 5 = 3

The formula for n-th term is:
Un = a + (n - 1)b
      = 5 + 3(n - 1)
      = 3n + 2