Yes. Actually this shouldn't be a question if one understands the meaning of "trivial". Trivial basically means "the question has no need". One example of a trivial property is:
- Do human beings have brain?
There is no need to answer this question as it is trivially true- because all human beings have brain.
Now a non-trivial property would be
- Do human beings have intelligence?
Now, this need not be true for all human beings and hence non-trivial.
Now, coming to functional dependency we say A- > B, when the same A element always causes the same B element. i.e., whenever A element repeats B element also repeats. If A is a composite set (x,y) coming from attributes X and Y and B is the attribute Y (hence B ⊂ A), we are sure than whenever the A element repeats the B element also repeats. That is, the functional dependency cannot be violated whatever be the elements - hence TRIVIAL.