Răspuns:
(2x+1)/(x-2)
x-2 I 2x+1
x-2 I 2x-4=> x-2 I 2x+1-2x+4
x-2I 5
x-2∈D₅
x-2=D₅{-5,-1,1,5}
x={-3,1,3,7}
I=divide
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3km=300000cm
300000:75=4000 pasi face tatal
300000:50=6000 pasi face fiul
6000-4000=2000 de pasi face mai mult fiul decat tatal