Rumus suku ke-15 dri barisan bilangan berikut 8, 6, 4, 2... adalah

8, 6, 4, 2...

Ditanya suku ke 15

Jawaban :

Nilai a = 8
Nilai b = 6 - 8 = -2

Maka, U15
= a + (n-1)b
= 8 + (15-1)(-2)
= 8 - 28
= -20 ✔

a = 8
b = 6 - 8 = -2
U15...?

U15 = a+14b
U15 = 8+14(-2)
U15 = 8-28
U15 = -20