Is the prostration of forgetfulness (sujud al-sahw) obligatory for one who forgot and did not recite aloud in a prayer where recitation is audible (salat al-jahriyyah)?

Recitation aloud and silently are from the Sunnahs of prayer, and each has its own place. So, whoever recites silently in a place where recitation should be aloud, or recites aloud in a place where recitation should be silent, it is sunnah for him to perform the prostration of forgetfulness (sujud as-sahw), but it is not obligatory upon him.