Use mathematical logic to prove this proposition

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The discussion focuses on proving the proposition A implies C given the premises A implies B and B implies C, using axioms from a Hilbert System without employing the deduction theorem or Modus Ponens. The axioms provided include implications that form the basis for the proof structure. The proof is constructed by relabeling the variables and applying the axioms systematically to derive the desired conclusion. Key steps involve utilizing the axioms to establish the relationships between the propositions. The conclusion confirms that A implies C follows logically from the initial premises.
solakis1
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Given the following axioms:
1) ##P\implies(Q\implies P)##
2) ##((P\implies(Q\implies R))\implies((P\implies Q)\implies(P\implies R))## Where ##P,Q,R## are any formulas
3)##(\neg P\implies\neg Q)\implies (Q\implies P)## then prove:

##\{A\implies B,B\implies C\}|- A\implies C##
Without using the deduction theorem and as a rule of inference M.ponens
 
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Your OP outlines the axioms of a Hilbert System. Go to the wiki page on Hilbert Systems and search "(HS2)" to see a proof of the following proposition from those axioms using Modus Ponens as rule of inference.
$$(p \to q) \to ((q \to r) \to (p \to r))$$
Relabel ##p,q,r## as ##A,B,C## to get
$$(A \to B) \to ((B \to C) \to (A \to C))$$
Then we have:
\begin{align}
&\vdash(A \to B) \to ((B \to C) \to (A \to C))\\
(A \to B), (B \to C)&\vdash(A \to B) \to ((B \to C) \to (A \to C))\\
(A \to B), (B \to C)&\vdash A\to B\quad\quad\textrm{[1st axiom]}\\
(A \to B), (B \to C)&\vdash(B \to C) \to (A \to C)
\quad\quad\textrm{[Modus Ponens on 3, 2]}\\
(A \to B), (B \to C)&\vdash B\to C \quad\quad\textrm{[2nd axiom]}\\
(A \to B), (B \to C)&\vdash A \to C
\quad\quad\textrm{[Modus Ponens on 5, 4]}
\end{align}
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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