a)
[tex]4x^{2}\geq 25\\\\4x^{2}-25 \geq 0\\\\M. \ zerowe:\\\\(2x+5)(2x-5) = 0\\\\2x+5 = 0 \ \vee \ 2x-5 = 0\\\\2x = -5 \ \vee \ 2x = 5\\\\x = -\frac{5}{2} \ \vee \ x = \frac{5}{2}\\\\a > 0, \ to \ ramiona \ paraboli \ zwrocone \ do \ gory\\\\\boxed{D: \ x \in(-\infty; -\frac{5}{2}\rangle \ \cup \ \langle\frac{5}{2}; +\infty)}[/tex]
b)
[tex](2x+1)(x-2) < (x-2)(x+5)\\\\(2x+1)(x-2) -(x-2)(x+5) < 0\\\\(x-2)[(2x+1-(x+5)] < 0\\\\(x-2)(2x+1-x-5) < 0\\\\(x-2)(x-4) < 0\\\\M. \ zerowe:\\\\x-2 = 0 \ \vee \ x-4 = 0\\\\x = 2 \ \vee \ x = 4\\\\a > 0, \ to \ ramiona \ paraboli \ skierowane \ do \ gory\\\\\boxed{D: \ x \in (2;4)}[/tex]
