This is LaTeX code:
[latex]
|{(a_{l+1}-(s_{l+1}-1))\over {(s_{l+1}-1)a_{l+1}}}|={{k_*-1}\over {(s_{l+1}-1)(s_{l+1}-k_*)}}\geq{1\over {(s_{l+1}-1)(s_{l+1}-k_*)}}>{1\over {(s_{l+1}-1)(s_{l+1})}}
[/latex]