[tag=IN] [lemma=simpler] [lemma=case] □
[tag=IN] [lemma=simpler] [lemma=case] [□]
[tag=IN] [lemma=simpler] [lemma=case] □?
Such option valuations may , in simpler cases , be based on analytical closed forms involving special functions , or , failing that , may require intensive numerical computation requiring some extensive programming .