There is no single authoritative source for mathematical notation. That said, there are a lot of common conventions. You could do worse than this NIST document

There is no single authoritative source for mathematical notation. That said, there are a lot of common conventions. You could do worse than this NIST document if it's just a notation question: https://dlmf.nist.gov/front/introduction https://dlmf.nist.gov/front/introduction Of course, if the real problem is that you need to learn some mathematical constructs, that is a different problem. The good news is that there's a lot of material online, the bad news is that not all of it is good... I often like Khan Academy when it covers the topic. I wish you luck!