Question

#jwb dgn cara!.........:(​

Answer 1

no 17)

s = 12

s'= 3s

s'= 12(3) = 36

berarti

1/f = 1/s + 1/s'

1/f = 1/12 + 1/36

1/f = (3+1)/36

4f = 36

f = 9

Jari" kelengkungan = R =2f = 2(9) = 18 cm