The Variational Method (QM approximation) | Quantum Mechanics

In this video, I introduce, prove, and demonstrate the variational method from quantum mechanics. A technique used to compute an upper bound on the energy of the ground state of a quantum system.
My Quantum Mechanics Lecture Series:
• Quantum Mechanics Lect...
Clarification: I ignored the negative root because it would not lead to a smooth trial function, and would therefore be much worse than the simple square guess that we were trying to improve on. Also, one in general has to check that the root one does select actually is a minimum, a step that I skipped here.