Jawabanmu

2014-02-10T19:12:42+07:00
R?
u4?
a) a=2 ; u5=162
ar^4=162
2r^4=162
r^4=162/2
r^4=81
r=3

u4=ar^3
2.3^3
2.27=54

b)a=4 ; u3=64
ar^2=64
4r^2=64
r^2=64/4=16
r=4

u4=ar^3
4.4^3=4^4
=256