Solve the inequality LaTeX:  \displaystyle \frac{2}{x^{2} - 4}<\frac{2}{x^{2} + 7 x + 10}

Getting zero on one side and factoring gives LaTeX:  \displaystyle - \frac{2}{\left(x + 2\right) \left(x + 5\right)} + \frac{2}{\left(x - 2\right) \left(x + 2\right)}< 0 . This gives the least common denominator as LaTeX:  \displaystyle \left(x - 2\right) \left(x + 2\right) \left(x + 5\right) . Building each fraction to get the common denominator gives LaTeX:  \displaystyle \frac{2 x + 10 - (2 x - 4)}{\left(x - 2\right) \left(x + 2\right) \left(x + 5\right)} < 0 . Simplifying gives LaTeX:  \displaystyle \frac{14}{\left(x - 2\right) \left(x + 2\right) \left(x + 5\right)}<0 . The inequality can change signs at the zeros of the numerator, LaTeX:  \displaystyle \emptyset , or the zeros of the denominator LaTeX:  \displaystyle \left\{-5, -2, 2\right\} . Making a sign chart gives: This gives the solution LaTeX:  \displaystyle \left(-\infty, -5\right) \cup \left(-2, 2\right)