Professor, Department of Mathematical Sciences University of Puerto Rico at Mayaguez  Office: Monzón 218 Office hours: Tue-Thu 9:00am-10:30am, 1:00pm-2:30pm  (787)832-4040 x 3171 portna@gmail.com, arturo.portnoy@upr.edu

Links:

• Free mathematics textbooks
• Some more free mathematics textbooks
• Interesting graphing applets for Calculus, Analysis and Differential Equations
• WiZiQ and BigMarker, two free virtual learning environments and Scribblar, a free virtual whiteboard.
  
• Khan Academy: pre-calculus, algebra and calculus videos that may be useful to review and study
• Calculus Videos: Very useful videos of single variable calculus lessons. Good for reviews! Another link to the same videos.
  
• Another set of useful mathematics videos.
• Free Calculus Textbook by Gilbert Strang
• Free Linear Algebra notes by Paul Dawkins
• Free Calculus Textbook by Jerrold Marsden and Alan Weinstein
  
• A video series of a complete Differential Equations course taught by an MIT professor
• A nice, free textbook for Differential Equations
• Olimpiadas Matemáticas de Puerto Rico