e urgeeeeeeeent
Dau corOana

Răspuns:
Explicație pas cu pas:
E(x) = (4x + 3)² + (2x - 4)(4x + 3) + (x - 2)²
E(x) = (4x + 3)² + 2(4x + 3)(x - 2) + (x - 2)²
E(x) = (4x + 3 + x - 2)² = (5x + 1)²
[tex] \sqrt{E(n)} \leqslant 3 \leftrightarrow - 3 \leqslant 5n + 1 \leqslant 3 \: \leftrightarrow - 4 \leqslant 5n \leqslant 2 \rightarrow \boxed{n = 0} \\ [/tex]