Can you not ommit the 'kan' for the same meaning? - 'hun tro ikke det'
No, that would translate to "She is not believing it." She may have the ability to believe it, but she refuses to. See what I mean?
Both "tro det" and "tro på det" are accepted. Is there a difference in meaning or usage?
Why is "Hun kan ei tro det" correct?
"Ei" is another form of "ikke." We took it out of best translations, so it won't appear again here.
When can it be used?
It's fairly uncommon compared to "ikke," but it is used interchangeably with "ikke."
Ah okay. Is it still accepted as a translation?