Pfau Library's databases are available from any computer connected to the campus network; you need not be in the library to use them. Off-campus, only currently registered CSUSB students will be able to use the databases, because they require a CSUSB log-in.
If you are currently registered at another university, be sure you check your university library's website--you may have access to the same databases without realizing it!
Ebooks are available for CSUSB users on the campus network. For tips on how to find them, check this video tutorial:
Pfau Library's books are discoverable in OneSearch:
Again, check the library web site for your home institution; you may already have access to many mathematics-related ebooks!