Uploaded October 2021 | Updated September 2026, 2 weeks ago

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This lecture is part of an online course on rings and modules.

We continue the previous lecture on complete rings by discussing Hensel's lemma for finding roots of polynomials over p-adic rings or over power series rings. We sketch two proofs, by slowly improving a root one digit at a time, and the other using Newton's method.

For the other lectures in the course see youtube.com/playlist?list=PL8yHsr3EFj52XDLrmvrFDgwcf6XOm2TEE