It's 'useless' trying to change her mind. = It's 'useless' to try to change her mind.
Drugs are 'useless' in treating the condition.
I made a 'useless' attempt at fixing the leak.
(..) dangerous relics... And there be a mysterious room called the Think Tank. I had to replace every part of my once-strapping... ...with this useless hunk of garbage ye see before ye. So if ye think it'd be a good idea to return... ...what idea have ye that be better... (..)2014 The Lego Movie
(..) So, uh, didn't catch your name... ...or anything about what you're, uh, up to. It's brilliant, sir, that you pretended to be a useless nobody... ...but you can drop the act with me. It's cool. - Watch out! - Hold on. We need to meet up (..)2014 The Lego Movie