Qual é a diferença entre It doesn't matter. e I don't mind. ?Você pode indicar exemplo de resposta.

it doesn't matter is more negative then i don't mind
the first is when you don't care about a certain situation or problem and you say to show that you're upset .example: your friend forgets to bring you back your computer ...you're upset but don't want to get into a fight ...so you say " it doesn't matter now...bring it tomorrow"
the second is to show a positive and polite attitude when presented with an inconvenience ...example : someone asks you to help with preparation for a party and then apologizes for the inconvenience you say : that's ok ...i don't mind helping ...
these are just simple examples to help you understand better the difference