Tolong nomor9 yaaa pke cara yaa Trimakasih:)

Diket : So = 8 cm
M = 1,5
Dit : f?
Jawab :
Si/So = M
Si = M x So = 1,5 x 8 = 12 cm
1/f = 1/Si + 1/So
= 1/12 + 1/8
= 2/24 + 3/24
1/f = 5/24
f = 24/5 = 4,8 cm

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