BS I.1.12: aanandamayo 'bhyaasaat
Sandhi-vigraha (removing of sandhi): aananda-mayaH; abhyaasaat The main sandhi rule for that suutra: When -aH is followed by a word that begins with a *short* a-sound, -aH changes to -o and the initial 'a' disappears. Please, don't be discouraged! That's one of the weirdest rules of sandhi. Most of them are rather, well, "logical". (We gots to keep in mind that this change has no effect whatsoever on the *meaning* of the sentence in question...) Has *some* resemblance with English "I am" > "I'm", only in Sanskrit the change is (practically) obligatory.
