There is no difference. You can read it how you like.

1) We use both readings, but we use いく in the spoken style while ゆく is more used in the written style. いく sounds colloquial and casual to me, and ゆく sounds a bit more bookish and maybe poetic. 2) 行った, the past tense form of 行く, is read as いった, not ゆった. Likewise, 行って, the ren'you-kei form of 行く, is read as いって, not ゆって.

The meaning doesn't change at all. The impression might change, however. In my opinion, "iku" is more common and appropriate especially in formal situations. On the other hand, "yuku" sounds more poetic and is preferred for literature or song. I can think of many songs that read 行く as "yuku."

行くはゆくとの意味が同じです。ちゃんと覚えてくださいね。

so, it doesn't matter if we read it as iku or yuku. there's no different meaning in it?