Question

прошу очень сильно решите это:
-4x²+13x-3≥0​

Answer 1

$\displaystyle -4x^2+13x-3\geq 0\\-4x^2+12x+x-3\geq 0\\-4x(x-3)+x-3\geq 0\\(x-3)(-4x+1)\geq 0\\\\ \left \{ {{x-3\geq 0} \atop {-4x+1\geq 0}} \right. \left \{ {{x\geq 3} \atop {x\leq \frac{1}{4} }} \right. \\\\ \left \{ {{x-3\leq 0} \atop {-4x+1\leq 0}} \right. \left \{ {{x\leq 3} \atop {x\geq \frac{1}{4} }} \right.\\\\ x\in \phi , x\in [\frac{1}{4},3] \\ x\in [\frac{1}{4},3]$