[randmeerkat]

> Whenever I try to catch up with maths (in Khan Academy and elsewhere), I always end up in an awkward state where I keep recursively researching less and less advanced subjects because of gaps of various sizes in my fundamental knowledge. It's incredibly demotivating.

Try this course: https://www.edx.org/course/college-algebra-and-problem-solvi...

It uses the ALEKS system which identifies your weak points and brings you up to speed. Take notes during the process so you have something to reference in the future and won’t forget what you learned.

After you knock out the algebra course you’ll be ready for the precalculus course: https://www.edx.org/course/precalculus

The ALEKS system in the Precalculus course will also remediate anything you forgot from the Algebra course.

Hopefully this will help give you the confidence to go after more advanced maths once you finish both courses. Be kind to yourself, math, like anything, is a skill, it takes time and practice.