Peano Definition and 17 Threads

Following is a set of Peano postulates I am using as defined in the book "Th real numbers and real analysis" by Ethan Bloch. There exists a set ##\mathbb{N}## with an element ##1 \in \mathbb{N}## and a function ##s: \mathbb{N} \rightarrow \mathbb{N} ## that satisfy the following three...

I have to prove the associative law for addition ##(a+b) + c = a + (b+c)## using Peano postulates, given that ##a, b, c \in \mathbb{N}##. Now define the set $$ G = \{ z \in \mathbb{N} |\forall\; x, y \in \mathbb{N} \quad (x + y) + z = x + (y + z) \} $$ Obviously, ## G \subseteq \mathbb{N} ##...

So I was just writing a proof that every natural number is either even or odd. I went in two directions and both require that 1 is odd, in fact I think that 1 must always be odd for every such proof as the nature of naturals is inductive from 1. I am using the version where 1 is the smallest...

As I understand Hilbert's omega rule for a first-order proposition P over the natural numbers, P(0) &P(1) &P(2) &... ⇒ ∀n∈ℕ P(n) :star: which seems to be the same as ω-consistency. Is there a difference? Further, the axiom schema of induction has each axiom for a proposition P over the...

Homework Statement Let, m, n be natural numbers and S(n) the succesor of n. If S(n)*m = nm + m Prove that m*S(n) = nm + m Homework Equations The Attempt at a Solution

Problem: y'=((x-1)/(x^2))*(y^2) , y(1)=1 . Find solutions satisfying the initial condition, and determine the intervals where they exist and where they are unique. Attempt at solution: Let f(x,y)=((x-1)/(x^2))*(y^2), which is continuous near any (x0,y0) provided x0≠0 so a solution with y(x0)=y0...

Hello everyone. I wanted to prove the following theorem, using the axioms of Peano. Let ##a,b,c \in \mathbb{N}##. If ##ac = bc##, then ##a = b##. I thought, this was a pretty straightforward proof, but I think I might be doing something wrong. Proof: Let ##G := \{c \in \mathbb{N}|## if ##a,b...

It seems that learning PA is necessary if you want to understand the relationship between logic and math. Should I track down this book at the library, a chore which will take up an hour of my precious time The principles of arithmetic, presented by a new method" in Jean van Heijenoort...

Is it possible to define sets from just the peano axioms? Usually when people use the peano axioms as the basis of their math they just assume the existence of sets but without axioms regarding sets we technically shouldn't just say they exist. Oh, also there are two versions of the...

Hello there, First off: I realize this is not a history of math sub-forum, but I could not find any such thing. Now, secondly: I'm writing an essay on the history axiomatic systems, and I found one or two sources that indicate that Giuseppe Peano was in fact influence by Euclid.I wonder...

i am studying real analysis from terence tao lecture notes for analysis I. http://www.math.ucla.edu/~tao/resource/general/131ah.1.03w/ from what i understand , property is just like any other statement. for example P(0.5) is P(0) with the 0s replaced with 0.5 . so the notes says (assumes ?)...

I have to do the following using these axioms PA1-7, the others below it are previously proved results I can use too. [Sa] means the successor of a. Base Case: y = S0 x.S0 = S0 → x.0 + x = S0 → 0 + x = S0 → x = S0 & y=S0 Now the induction step is usually y=a to y=Sa, however this does...

Let (N, s(n), 0) be a Peano space. That is, N=\{1,2,3,\dots \} is a set in which http://en.wikipedia.org/wiki/Peano_arithmetic" can be used. We can then define: 0=\varnothing, 1=\{0\}, 2=\{0,1\},\dots \implies n=\{0,1,2,\dots ,n-2,n-1\} s(a)=a\cup \{a\}\implies s(a)=a+1 From here we...

I'm working on a proof of the Peano Existence Theorem. It says that: For a continuous ordinary differential equation dx/dt = f(x, t), where x is in R^n and f is continuous on |t-t_0|<=a, ||x-x_0||<=b when you have an initial value, x(t_0) = x_0, then there is a solution on |t-t_0|<= c...

Homework Statement Show that the natural numbers satisfy commutativity of multiplication and distributivity of multiplication over addition. Homework Equations The Attempt at a Solution I'm wondering if there is any potential circularity in this reasoning. I proved distributivity...

Can anyone point me towards an online link or some books where I can study these bad boys? I am supposed to write like a 5-10 page paper on Peano curves in which I prove a few interesting things regarding them.

I'm an engineer, not a mathematician... the professor has assigned several proof questions, and I'm having difficulty answering them... (This may need to be moved to homework help, but the topic is unusual, so I thought I'd get better response here) Terminology: v is a join operation...