Tolong dijawab nomor 9 dan 10 !

No.9
3 jam = 3 x 60 = 180 menit / 20 = 9 kali
U1 = 10
10, 20, 40, 80, 160, 320, 640, 1280, 2560 (caranya dikalikan 2 sembilan kali)
Jadi ada 2560 bakteri.

No.10
4, 7, 11,
+3, +4
+1

2a=1
a=1/2

3a+b=3
b=3- 3/2
b=1/2

a+b+c=4
c=4-1
c=3

Un = a.n kuadrat + bn +c
U25 =1/2.25kuadrat + 1/2.25 +3
=312.5 + 12.5 + 3
=328