I'm restudying math through khan academy because I believe my level is very low, but I was wondering if it's better to learn only the math necessary to do something at the moment (such as a parabola of a bullet) or to follow through a textbook or site to learn the theory with  some practice.

There are books dedicated to math for games and graphics, you should check them out.  Search for 'math for game programming'.  Amazon will let you browse through the table of contents so you can see if its what you need.  There are also books on physics and other more specialized topics.

What is your current level of mathematics? Algebra?  Geometry?  Calculus?

this has always been a great resource for game dev math.  it is a very long youtube playlist.  each video on the order of 5 to 10 mins

I'll watch it, thanks djsteffey. Now i'm at algebra 1 and geometry, I'm doing these 2 at the same time.

6 hours ago, Luhan M. said:

I'll watch it, thanks djsteffey. Now i'm at algebra 1 and geometry, I'm doing these 2 at the same time.

Well finish those up first.  Then consider getting one of the books on math for game programming if its what you need.  Did you take a look at them?  There are like three or four of them IIRC.  There are tutorials on the internet as well, but I don't know any of hand since I haven't looked for them for a while now.  For the simpler math I would search for tutorials on the internet, but for the more complicated stuff its nice to have a reference for yourself as well.  I still have my math textbooks from college.

Since nobody seems to have mentioned it: Do lots of problems. Math is about solving problems. Good math books have problems at the end of each chapter. Take some time and try to solve them. That's the part of the book where you learn the most.

I got a degree in math and my primary way to study was to take a long list of problems and solve problems 7, 17, 27, 37... If along the way I discovered I needed something I didn't know, I would read the text about it, with the specific problem in mind. If I had time I would pick another digit and do another pass (say 4, 14, 24, 34...).

3 hours ago, Infinisearch said:

Well finish those up first.  Then consider getting one of the books on math for game programming if its what you need.  Did you take a look at them?  There are like three or four of them IIRC.  There are tutorials on the internet as well, but I don't know any of hand since I haven't looked for them for a while now.  For the simpler math I would search for tutorials on the internet, but for the more complicated stuff its nice to have a reference for yourself as well.  I still have my math textbooks from college.

I did some research and found these books:

Foundations of Game Engine Development, Volume 1: Mathematics:

https://www.amazon.com/Foundations-Game-Engine-Development-Mathematics/dp/0985811749/

Game Physics Cookbook:

https://gamephysicscookbook.github.io

3D Math Primer for Graphics and Game Development:

https://www.amazon.com/Math-Primer-Graphics-Game-Development/dp/1568817231/ref=sr_1_2?s=books&ie=UTF8&qid=1512071016&sr=1-2&keywords=math+game+programming

Mathematics for 3D Game Programming and Computer Graphics:

https://www.amazon.com/Mathematics-Programming-Computer-Graphics-Third/dp/1435458869/ref=sr_1_1?s=books&ie=UTF8&qid=1512071016&sr=1-1&keywords=math+game+programming

Someone advocates in favor of one of these? Because is very expensive to ship to Brazil, so probably for now, I only can buy one of them.

Don't forget this gem:

https://www.amazon.com/Essential-Mathematics-Games-Interactive-Applications/dp/0123742978/ref=sr_1_3?ie=UTF8&qid=1512073939&sr=8-3&keywords=game+programming+essentials+math

3 minutes ago, Mike2343 said:

Don't forget this gem:

https://www.amazon.com/Essential-Mathematics-Games-Interactive-Applications/dp/0123742978/ref=sr_1_3?ie=UTF8&qid=1512073939&sr=8-3&keywords=game+programming+essentials+math

There is a newer version of that book.

48 minutes ago, Luhan M. said:

Someone advocates in favor of one of these? Because is very expensive to ship to Brazil, so probably for now, I only can buy one of them.

Before you look for endorsements you should look at the table of contents of each and see if it has what you need.  Notice the 3d in alot of the titles... if you're doing 2d then they might not be of as much help... skipping things like the seperating axis theorem.

12 hours ago, Infinisearch said:

 

Before you look for endorsements you should look at the table of contents of each and see if it has what you need.  Notice the 3d in alot of the titles... if you're doing 2d then they might not be of as much help... skipping things like the seperating axis theorem.

I thought that most of the things applied in 3D somehow could be applied to 2D as well. I'm just looking for a basic book to start, because in most of them the prerequisites judged by the author I would have to wait a little bit until I advance in my study through khan academy.