Jawabanmu

2014-06-10T15:21:00+07:00
U7/U4 = a x r^{6} / a x r^{3}
32/4 =  r^{3}
      8      = r³
      r       = ∛8 = 2

U4 = a x 2³
 4  = a x 8
 a  = 4/8 = 1/2

U10 = 1/2 x  2^{9}
U10 = 1/2 x 512
U10 = 256