Question

Resolver a inequação:
$x (x + 1) - 2 (3x - 1) \leq x (1 - x)$

Answer 1

$x(x + 1) - 2(3x - 1) \leq x(1 - x) \\\\ x^2 + x - 6x + 2 \leq x - x^2 \\\\ 2x^2 - 6x + 2 \leq 0 \\\\ x^2 - 3x + 1 \leq 0 \\\\\boxed{S = \left \{ x \in \mathbb{R} | \frac{3 - \sqrt{5}}{2} \leq x \leq \frac{3 + \sqrt{5}}{2} \right \}}$