Diketahui suatu barisan aritmatika 9,18,36,... a.rumus suku ke-n b.nilai suku ke-10

9, 18, 36,...
suku pertama a = 9
r = 18/9 = 36/18 = 2
Un = ar^(n 1)
= 9.2^(n-1)
= 9/2.2^n
U10 = 9/2.2^10
= 9.2^9
= 9x512
= 4.608