Hello, I am in my first semester of graduate school after 4 years being out of school. I brushed up on calculus but some essentials are gone. I was doing kinetic problems and had to find concentrations. I automatically knew to get rid of ln x I need to use an exponential. My mind went blank when I saw 1/x. I had to google it after a couple minutes and it showed me 1/(1/x) to get x which I can't believe I forgot. Are there any good reference materials I can use to brush up on these kind of skills? I looked through a couple things like Langs Basic Mathematics but that wasn't even in there.