Question

Cum se rezolva problema aceasta:

Aratati ca $x^2+x+1\ \textgreater \ 0$ ,∀ x ∈ R.

Answer 1

============================

Answer 2

$\it x^2+x+1 = x^2+x+\dfrac{1}{4} +\dfrac{3}{4} =\left(x+\dfrac{1}{2}\right)^2 +\dfrac{3}{4} \geq\dfrac{3}{4} \ \textgreater \ 0$