Question

Minta tolong no 8 dan 9 yaa pakek caranya ..

Answer 1

R = 4860/20 = 243
r pangkat 5 = 243
r = 3

20(3 pangkat 6 -1)
——————————
3-1

20(728)
------------
2
=7280 cm
=72,8 m (b)

9) u1 = 147
Un = 273
b = 7

273 = 147 + (n-1)7
273 = 147 + 7n-7
273 = 140 + 7n
7n = 273 - 140
7n = 133
n = 19

Sn = n/2 (U1 + Un)
= 19/2 (147+273)
=19/2 (420)
= 3990 (d)