Is expiation obligatory for one who broke his repeated oaths, after having sworn by Allah in anger not to eat or do something, and then ate or did it after he calmed down, while forgetting the number of times he broke the oath?

A Muslim should avoid excessive swearing by Allah without a valid reason. The oath of an angry person is binding if he is aware of what he is saying. Whoever breaks many oaths and does not know their number should continue to offer expiations until he is reasonably certain that his obligation has been fulfilled. The expiation for an oath is: feeding ten poor people, or clothing them, or freeing a slave; and if one is unable to do so, then fasting for three days.