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Using Peano's axioms to disprove the existence of self-looping tendencies in natural numbers

Let me clarify by what I mean by "self-looping". So, we know that Peano's axioms use primitive terms like zero, natural number and the successor operation. Now, I want to prove that the ...
Aryaan's user avatar
  • 283
0 votes
2 answers
37 views

Confusion about the validity of the proof of Trichotomy of order for natural numbers in Tao's Analysis

It's well-known that in Tao's Analysis I P28, he provides a provement of Trichotomy of order for natural numbers as follows. Denote the number of correct propositions among the three (i.e. $a<b,\ ...
Richard Mahler's user avatar
0 votes
1 answer
82 views

Are the axioms of analysis a combination of Peano axioms and set theory axioms?

Observing the use of mathematical induction in proving the finite version of the axiom of choice, I began to ponder. Why is mathematical induction from Peano axioms employed to prove facts about sets? ...
ju so's user avatar
  • 297
1 vote
1 answer
53 views

Proof that the elements are distinct with Peano's axioms.

Consider the function successor function $s: \mathbb{N} \to \mathbb{N}$ and the Peano's axioms: P1) $s: \mathbb{N} \to \mathbb{N}$ is injective. P1) $\mathbb{N} \setminus s(\mathbb{N})$ has only one ...
Croos's user avatar
  • 1,819
1 vote
1 answer
85 views

A corollary of two lemmas regarding the definition of addition of real numbers

In Terence Tao's Analysis, he mentioned that two lemmas contribute to a corollary, which I can not fully understand. To start with, Tao defined two axioms of addition: 0 + m := m (n++) + m := (n+m)++...
Dinoman's user avatar
  • 862
0 votes
1 answer
104 views

Construction of the addition function

I am reading a book called Analysis I by Herbert Amann and Joachim Escher. I am currently stuck on page 33 where they construct the addition operator using functions. One property the addition ...
Roger Crook's user avatar
2 votes
2 answers
110 views

Which is the axiom: well ordering principle, principle of induction, both, or none?

From analysis 1 by Terence Tao, I learn that the principle of induction is a peano axiom. In many other analysis books, like analysis by Bartle and Sherbert, the well ordering principle is used to ...
Michael Tamajong's user avatar
1 vote
1 answer
141 views

Proof critique of least number principle, please!

I am independently working through Elliot Mendelson's "Number Systems and the Foundations of Analysis," which I find very well-written and rigorous, along with providing a healthy set of ...
Cyrus's user avatar
  • 368
1 vote
1 answer
377 views

Function by recursion on a set $X$ satisfy Peano's axioms

I've been stuck on this theorem for like two days and I still don't really get it. I'm reading the construction of natural numbers using "classic set theory for guided independent study", ...
cekami7844's user avatar
2 votes
1 answer
347 views

Proof of Edmund Landau's Foundation of Analysis [duplicate]

The theorem is as following: The proof was split into two parts, namely: Uniqueness and Existence, I have hard time understanding the existence part: Namely: in the 10-12th line, what did Edmund ...
hteica's user avatar
  • 428
0 votes
3 answers
133 views

Prove if $x \neq 1$ then there exists exactly one $u$ such that $x=u'$

While I'm reading E. Landau's Grundlagen der Analysis (tr. Foundations of Analysis, 1966), I couldn't understand the proof of Theorem 3 at the segment of Natural Numbers which I've quoted below. ...
delphinarum's user avatar
1 vote
2 answers
768 views

How can I prove this proposition from Peano Axioms: (Cancellation law). Let a, b, c be natural numbers such that a + b = a + c. Then we have b = c.

Peano Axioms. Axiom 2.1 $0$ is a natural number. Axiom 2.2 If $n$ is a natural number then $n++$ is also a natural number. (Here $n++$ denotes the successor of $n$ and previously ...
Henrique's user avatar
2 votes
1 answer
2k views

Proving distributive law of natural numbers

Is my proof correct? If we define multiplication for natural numbers as $a \times S(b) = (a \times b) + a$ $a \times 0 = 0$ And addition as $a + 0 = a$ $a + S(b) = S(a+b)$ Where $S(n)$ is the ...
user525966's user avatar
  • 5,651
1 vote
1 answer
70 views

Are my proofs correct for basic addition properties for natural numbers?

Are my proofs correct? Additive Identity: $a + 0 = a$ Definition of Addition: $a + S(b) = S(a + b)$ where $S(a)$ is the successor of $a$. Claim: $0 + a = a$. Base Case: When $a=0$, we have $0 + ...
user525966's user avatar
  • 5,651
0 votes
2 answers
553 views

Peano axioms-Mathematical Induction

This is from the book we're using in my Analysis class: The Peano Axioms of the set $\Bbb N$ are: $1.$ Every natural number has a successor, i.e. $\forall n\in\Bbb N, \exists!s(n)\in\Bbb N$ ...
lmc's user avatar
  • 2,411

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