Page 14 - E-MODUL BARISAN DAN DERET

BARISAN DAN DERET SEMESTER 1

b) 1, 9, 25, 49, ….

Jawab:

a) 4, 6, 8, 10, ….
= 4 = 2 + 2 = (2 × 1) + 1
1
= 6 = 4 + 2 = (2 × 2) + 1
2
= 8 = 6 + 2 = (2 × 3) + 1
3
= 10 = 8 + 2 = (2 × 4) + 1
4
…
= (2 × ) + 2

= 2 + 1

b) 1, 9, 25, 49, ….

2
= 1 = ((2 × 1) − 1)
1
2
= 9 = ((2 × 2) − 1)
2
2
= 25 = ((2 × 3) − 1)
3
2
= 49 = ((2 × 4) − 1)
4
2
= ((2 × ) − 1)

= (2 − 1)
2

Contoh 5:

1
Suatu barisan bilangan dengan rumus = ( )

2
a) Tulis empat buah suku pertamanya
b) Berapa suku ke-5 dan ke-7?

Jawab:

1
a) = ( )

2
1 1
1
= ( ) =
1
2
2
E-MODUL MATEMATIKA UMUM KELAS XI KD 3.6 13