Jawabanmu

2014-03-11T17:24:13+07:00
Rumusnya 1/f = 1/sob+1/sob'
diket Sob : 100 cm
         f : 50 cm
1/Sob' = 1/f - 1/Sob
1/Sob' = 1/50 - 1/100
1/Sob' = 1/100
Sob' = 100 cm

oiya : cuman ngasih tau , kalo cermin cembung fokusnya bernilai negatif yaa

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