Jawabanmu

2014-05-13T18:50:18+07:00
Dik: s=2cm
      f=10 cm
dit:  s'..?
=1/s'=1/f - 1/s
=1/s'=1/10 - 1/2
=1/s'=1/10-1/2
=1/s'= -8/20
=s'=20/8= -2,5 cm

2014-05-13T18:52:08+07:00
1/f = 1/s + 1/s'

1/2 + 1/s' = 1/10
1/10 - 1/2 = 1/s'
1 - 5 = -4/10 = 10/-4 = -2,5 cm
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