[tex]4x^{2}+2x-1 < 0\\\\\Delta = b^{2}-4ac = 2^{2}-4\cdot4\cdot(-1) = 4 + 16 = 20\\\\\sqrt{\Delta} = \sqrt{20} = \sqrt{4\cdot5} = 2\sqrt{5}\\\\x_1 = \frac{-2-2\sqrt{5}}{8} = \frac{-1-\sqrt{5}}{4}\\\\x_2 = \frac{-2+2\sqrt{5}}{8} = \frac{-1+\sqrt{5}}{4}\\\\a > 0, \ ramiona \ paraboli \ skierowane \ do \ gory\\\\x \in (-\infty;\frac{-1-\sqrt{5}}{4}) \ \cup \ (\frac{-1+\sqrt{5}}{4}; +\infty)[/tex]
