Those situations where Talaaq takes place

Husband signing divorce letter

Q: In a heated argument with my husband, I wrote out a letter of divorce stating that he (his name) hereby issues me (my name) with a divorce and forced him to sign under his name. He signed in anger of what I was asking. I know that this is wrong. I would like to know if it constitutes to a divorce as I do not want to live in sin.

Divorce via sms

Q: My husband send me divorce on sms. He give me divorce not in front of me. He just write I divorce you three times and send to my cell phone number by sms. Is divorce valid?