Advance Engineering Mathematics
Here's a developing library of the AMS for open mathematical literature:
Seems to be nice, but has this annoying recaptcha nonsense :-((((.
Yes, but could have been worse "u9I0zX". It's only a checkbox and remember "Geschenktem Gaul ...". I've found some contributions from Toronto. Not the worst address.
A free source for university or college textbook :)
My math is the worst in all my subjects ,
Math text books that are free and can be read online or can be downloaded as ".pdf" :
a really good introduction to discrete mathematics. Book is available for free, or you can purchase on Amazon for a small fee. I really liked the chapter on logic and proof.
My high school son is currently enrolled in a Linear Algebra class at a pretty highly regarded liberal arts college in our town.
They follow Hefferon's Linear Algebra. The entire book (3rd edition) is available online for free:
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