You don't need to read a ton of books or know any math at all really - the basic answers they are typically looking for are patterns you can spot with no knowledge of logarithms what so ever.
Spend a few days and you will just recognise, "oh hey I've a nested loop here, it's likely O(n2)!" That's really all it takes, and there are only 4-5 main classifications most interview code falls into, all of which can be spotted without knowing what a logarithm is. If I had interviewed you, I would not be impressed you hadn't understood this at such a basic level either, personally. The rest of us making a full time living at software engineering have to learn it to pass interviews at top companies too!
Spend a few days and you will just recognise, "oh hey I've a nested loop here, it's likely O(n2)!" That's really all it takes, and there are only 4-5 main classifications most interview code falls into, all of which can be spotted without knowing what a logarithm is. If I had interviewed you, I would not be impressed you hadn't understood this at such a basic level either, personally. The rest of us making a full time living at software engineering have to learn it to pass interviews at top companies too!