Jawabanmu

2014-05-29T19:43:20+07:00
1/f = 1/s + 1/s'
1/6 = 1/18 + 1/s'
1/6 - 1/18 = 1/s'
3/18 - 1/18 = 1/s'
2/18 (1/9) = 1/s'
19 = s'
1 2 1
2014-05-29T19:47:09+07:00
1/s' = 1/f - 1/s
1/s' = 1/6 - 1/18
1/s' = 2/18
1/s' = 1/9
s' = 9

Perbesaran = s' : s = 9 : 18 = 0,5 kali
1 3 1