$\displaystyle \left(- \frac{\sqrt{13}}{4} \right)$\displaystyle \left(- \frac{\sqrt{13}}{4} \right)

$\displaystyle \left(- \frac{1}{2} \right)$\displaystyle \left(- \frac{1}{2} \right)

$\displaystyle \frac{1}{2}$\displaystyle \frac{1}{2}

$\displaystyle \frac{\sqrt{13}}{4}$\displaystyle \frac{\sqrt{13}}{4}