Those situations where Talaaq takes place

Issuing a talaaq while being forced

Q: My elder brother, recently and was forced to get divorced from his in laws. He was under so much pressure from them, and he was alone at his rented house, and they all forced him to say yes for the divorce. 

But now he is saying that he has not said from his true heart to his wife that I need the divorce from her. So please advise if the divorce is done on his wife or not, because my brother is saying that he has not given her divorce by his heart, but was under pressure from his in laws.

Issuing three talaaqs in the absence of one's wife

Q: I constantly have waswasa regarding different things, such as fears of losing important things and intrusive thoughts about divorce. 

Recently, while driving alone, I had thoughts of talaq, and I became worried about accidentally uttering the word and losing my wife. To counter these thoughts, I ended up saying the statement three times "main tumhy talaq deta hon" with my wife's name, thinking it would stop my mind from repeating it in front of her. 

However, I later read that divorce in isolation might still be valid. I also consulted an Imam at the Masjid, who assured me that the talaq is not valid. I would appreciate your opinion on this matter.

Divorcing one wife by saying her name but the another wife's name came to mind

Q: If a person has 2 wives and he, intending to divorce one says her name then explicit words of divorce like "Maryam I....(explicit words)" but at the time of sayings the words he has his other wife who he didn't want to divorce come to his mind.

Does it mean he accidentally gave divorce to the other wife (named Zainab) which he didn't intend to?

Using the word faarigh for divorce

Q: My husband and I were in an argument and both of us were very angry so when I said to him to give me talaq, he said you are farigh from my side but since I didnt know about the meaning of this word farigh, I didn't paid attention to it. After that 5 years passed and I also gave birth to our third baby.

Now, after asking one mufti about this, he said to me that the talaq was valid and when I asked my husband about this, he said I never said that you are farigh, rather I said farigh kardunga. Please help and I also dont remember it very much because years have passed.