Cautam f(x)= ax+b
f(x-3) = ax-3a+b= 2x-4-f(2) => egalam coef.lui x din ambii membri: a=2
Egalam si termenii liberi : -3a+b= -4-f(2) => f(2)=3a-b-4
Dar f(2) = 2a+b , deci 2a+b = 3a-b-4 a=2b+4 => 2=2b+4 => b=-1
Asadar f(x) = 2x-1
Verificare : f(2)=3 si f(x-3) = 2x-6-1=2x-4-3 = 2x-4-f(2)
