Salut,
x² + 4x + 4 = x² + 2·x·2 + 2² = (x + 2)².
Am aplicat formula de calcul prescurtat:
[tex]a^2+2\cdot a\cdot b+b^2=(a+b)^2.[/tex]
Green eyes.
"x la a doua plus 4x plus 4"
x^2 + 4x + 4
[tex]\it x^2 + 4x + 4 =x^2 + 4x + 2^2 =(x+2)^2[/tex]
