Online resources for learning Mathematics [closed]

Not sure if this is the place for it, but there are similar posts for podcasts and blogs, so I'll post this one. I'd be interested in seeing a list of online resources for mathematics learning.

As someone doing a non-maths degree in college I'd be interested in finding some resources for learning more maths online, most resources I know of tend to either assume a working knowledge of maths beyond secondary school level, or only provide a brief summary of the topic at hand.

I'll start off by posting MIT Open Courseware, which is a large collection of lecture notes, assignments and multimedia for the MIT mathematics courses, although in many places it's quite incomplete.

Solution 1:

The following reddit post has a decent list of math resources:

• http://www.reddit.com/r/math/comments/bqbex/lets_list_all_the_useful_free_online_math/

One site I did not see it their list that I've found very helpful:

• http://betterexplained.com/

Solution 2:

• Khan Academy, http://www.khanacademy.org/
• You'll find tons of explanatory videos from various branches of mathematics; plus, each subject is explained pretty good, and the videos are easy to follow

Solution 3:

Purplemath has a list for math lessons and tutoring. It's a list with various links and short reviews referring to tutoring and instructional resources.

Solution 4:

A useful one for undergraduate level maths is Mathcentre. It has useful background material for people studying maths, or who need some maths background for other courses.