Jawabanmu

2014-06-18T18:08:50+07:00
Diketahui:
S = 15 cm
S' = 60 cm

ditanya: titik api/fokus lensa

jawab: 1/F = 1/s+1/s'
1/f = 1/15 + 1/60
1/f = 5/60
f = 60/5 cm = 12 cm 
2014-06-18T20:59:08+07:00
1/f = 1/s+ 1/s'
1/f = 1/15 + 1/60
1/f = 4/60 + 1/60
1/f =5 /60
f= 60:5
f =12 cm

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