Question

RAPIIIIIIIIIIID !!!
Fie functia f : R - R , f(x) = 3-2x . Rezolvati inecuatia f(x) +4 < f(2x) , x € R

Answer 1

f(2x) = 3-2(2x)=3-4x
f(x)+4 = 3-2x +4= 7-2x
7-2x < 3-4x este echivalenta cu
4x-2x < 3-7
2x < -4
x<-2 Rezulta x ∈ (-∞,-2)