Question

Escribe explícita-mente quien es {x∈R ∶(3x+1)(x+2)=0}

Answer 1

{x∈R ∶(3x+1)(x+2)=0}

El conjunto de los x reales tales que:
(3x+1)(x+2) = 0

Resolviendo para x:
3x+1=0
x=-1/3

x+2 = 0
x=-2.

{x∈R ∶(3x+1)(x+2)=0} = {-1/3, -2}