Continuation: Complex Characteristic Roots; Undamped and Damped Oscillations -- Lecture 10. More discussions about oscillations with second-order ODEs.
Arthur Mattuck, 18.03 Differential Equations, Spring 2006. (Massachusetts Institute of Technology: MIT OpenCourseWare), http://ocw.mit.edu (Accessed November 26, 2008). License: Creative Commons BY-NC-SA.
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