Question Number 74508 by isra.pm07nov@gmail.com last updated on 25/Nov/19
$${li}=\overset{−} {{x}}−{t}_{{v}} ,\frac{\alpha}{\mathrm{2}}.\left(\frac{{s}}{\:\sqrt{{n}}}\right) \\ $$$${ls}=\overset{−} {{x}}+{t}_{{v}} ,\frac{\alpha}{\mathrm{2}}.\left(\frac{{s}}{\:\sqrt{{n}}}\right) \\ $$$$ \\ $$