Răspuns :
1 se reduce si obtinem 4x^2 +2x =0
Dam factor 2x si obtinem 2x(2x+1)=0
=> 2x=0 → x=0 € Z
=> 2x+1=0 → x=-1/2 nu apartine lui Z
4 x² + 2 x + 1 = 1
4 x² + 2 x = 1 - 1
4 x² + 2 x = 0 l : 2
2 x² + x = 0
x ( 2 x + 1 ) = 0
x₁= 0 ∈ Z
2 x + 1 = 0 ⇒ 2 x = - 1 ⇒ x₂ = - 1 / 2 ∉ Z