Bolzano and Cauchy's proof of Intermediate value theorem

Question

I am not sure if it is the right place to ask, but I have been searching for the proof of Intermediate value theorem made by Bolzano and by Cauchy and I am a bit confused because as I understood it the theorem was first proven by Bolzano and then Cauchy provided a proof of the theorem few years later and it was not the same proof. But where can I find the proofs of the theorem?

Answer 1

Proof by Bolzano is in Steve Russ - The mathematical works of Bernard Bolzano-Oxford University Press (2004), page 250.

Proof by Cauchy is in Robert E. Bradley, C. Edward Sandifer (auth.) - Cauchy’s Cours d’analyse_ An Annotated Translation-Springer-Verlag New York, (2009) page 32.