\[\frac{1}{3}x^{2} + \frac{1}{3}x - 4 < 0\ \ \ \ | \cdot 3\]
\[x^{2} + x - 12 < 0\]
\[D = 1^{2} - 4 \cdot 1 \cdot ( - 12) =\]
\[= 1 + 48 = 49\]
\[x_{1} = \frac{- 1 + \sqrt{49}}{2 \cdot} = \frac{- 1 + 7}{2} =\]
\[= \frac{6}{2} = 3;\ \ \ \ \ \]
\[x_{2} = \frac{- 1 - \sqrt{49}}{2 \cdot 1} = \frac{- 1 - 7}{2} =\]
\[= - \frac{8}{2} = - 4\]
\[Ответ:( - 4;3).\]