I dropped out of high school because it was interfering with my smoking pot and skateboarding schedule. A skatepark opened up by me (this was before concrete parks were the norm) and I managed to get a job building and maintaining ramps there. My friend and I had always built little kickers and quarter pipes but this was on a larger scale. So I went out and bought a book on geometry and taught myself circles and domes and stuff like that. Being interested in the outcome, not just the problem, was the thing that clicked for me. Once the interest was there, the work and study was fun. Since then, I've become a finish carpenter and specialize in odd trim details and complicated builds. So I guess my advice is to find a reason to learn it. Find that thing that makes it more than rote memorization and turns it into something more than that.

Khan Academy, Numberphile, and 3Blue1Brown

Wikipedia is rough for math. Anything remotely complex isn't really explained well to a layperson. What kind of math do you want to learn, and why? I can also recommend numberphile. Project euler is a cool way to teach yourself some math/programming concepts. I also can highly recommend the book "shape" by Jordan ellenberg to help build interest in geometry

I'm also half-math and half-IT person. I'd recommend you to start Competitive Programming, try to participate in the contests, solve Codeforces (https://codeforces.com/?locale=en) or Kattis (https://open.kattis.com) tasks, grasp Asymptotic notation, etc.

Math (and academical) formalism is a thing, Wikipedia also shows it. You just need to get used to it.

What you will probably learn in the University:

• Calculus (matrices, limits, derivatives, integrations)
• Discrete Math (sets, graphs, etc.)
• Algorithmic complexity and asymptotic notation
• Probabilities
• If you're lucky, you'll get Algebraic Structures (a.k.a Group Theory) that teaches the essential foundations of Math.

I've always been more interested in discrete part of math where real numbers do not exist (only rational numbers do).

Alternatively, if you're as mad as me, you can try doing side projects, like creating your own Computer Algebra System or Ray tracing algorithm from scratch. It is a good brain exercise.

Go to your Campus library, look for some books. My University library was a goldmine for me. Take notes. If you have a genius idea, don't hesitate to talk with your lecturers or the Dean, they can offer you scientific work.

Mathematics major here who is also a part-time mathematics tutor.

This is a question that plagues me too. Math is an absolutely gigantic subject! There’s statistics (probability, etc), combinatorics (counting things), calculus, differential geometry, topology, linear algebra, number theory. The list goes on. And what’s interesting is that they’re all connected! Knowing calculus, for example, can lead you to solve recurrence problems in combinatorics using generating functions, which i always thought was pretty neat. The idea of using the infinite to prove something finite.

My purpose here is not to overwhelm you, but to invite you to a whole new world. I’ve been obsessed with learning about everything in mathematics! I am actually in the opposite problem as you, as a math major transitioning into the tech field. I’ve always thought that learning computers is so much more interactive and hands-on, since you can make and build a project that you can show people. I think this is where you can focus on learning math: making something or building a project that interests you. That, and puzzles. Mathematics is not a spectator sport. You have to read some information, close your book, and put some pen into paper and fill in the gaps. Right now I’m going through Cryptohack puzzles to brush up on my number theory and learn its applications in cryptography.

Book learning is straightforward , but it has to be supplemented with exercises and putting pen into paper. Also, pick one field you’re interested in and stick with it. I hope this helps.

Khan academy

Just walk into a college class and start attending

Tbh just buy the textbook and work through it. That's what a lot of my college courses ended up consisting of

Either go with working through textbooks on your own, as has been stated by others, but that approach requires tons of discipline as the subject matter can get quite dry and frustrating at times. Or, I'd say ideally, enroll in courses at a local community college. The one I went to had four calculus classes, linear algebra and differential equations, along with statistics and I believe some kind of math programming course (my have just been part of other classes). So you cab get into fairly advanced stuff going that route.

If you want to learn even more after that, you'll have a solid basis to continue self study. Hell, you might even have a good start towards a bachelor's in math.

Depending on what you want to do in IT, you may not really need any math. If you are going to do programming, then yes, you'll need some advanced math.

Regardless of how you end up getting your information (whether textbooks or Khan academy or local school or what), the most important thing is that you have to do exercises. Learning math, especially more advanced stuff, is a lot of work. You just have to grind until you git gud, and it definitely will feel like a grind at times

Take a look at Engineering Mathematics by KA Stroud. It has a step-by-step approach with worked examples that might be useful to you. Even if you don't like the structure, it'll at least give you a comprehensive list of topics.

In addition to online options, taking courses at your local community college would be helpful. They often have remedial classes like this in the evening as well.

If you start studying at an university: They sometimes offer extracurricular maths courses. For people who need to brush up on their maths skills before the semester starts. At least where I live, they do.

I like the idea of just taking a textbook, skript or whatever and going through it. And making sure you actually understand it. No more more less. It's not learning for school or exams, it's for you.

I've started doing this weekly, tomorrow is day two! Through I will have to mix it with stuff for university classes.

Find a teacher, take private lessons. People are mentioning some online courses, but over long periods having a teacher can be more effective.

I really like Brilliant. It is really clear and interactive, the only real negative is the price.