Jawabanmu

2014-05-15T09:55:16+07:00
1/12 - 1/15 = 1/60 = 60
2014-05-15T10:05:12+07:00
 \frac{1}{f}  \frac{1}{s}  \frac{1}{s'}
 \frac{1}{12}  \frac{1}{15}  \frac{1}{s'}
 \frac{1}{s'}  \frac{1}{12}  \frac{1}{15}
 \frac{1}{s'}  \frac{5-4}{60}
 \frac{1}{s'}  \frac{1}{60}
s' = 60
#yg C

@jdikan yg trbaik yha.. makasih :)
2014-05-15T11:12:27+07:00
1/f = 1/s + 1/s'
f = fokus lensa cembung
s = jarak benda
s' = jarak bayangan

1/s' = 1/f - 1/s
1/s' = 1/12 - 1/15
1/s' = 5-4/60
1/s'=1/60
1/s' = 60
jawaban (c)