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2d
comment Finding a series of common multiples given arbitrary numbers
@CMCDragonkai I'm simply dividing an arbitrary common multiple by $m$. $r$ must also be a common multiple because $qm+r$ is, and $qm$ is (because $m$ is), thus subtracting the two we must get another common multiple.
2d
comment Understanding mathematical texts
I generally consider that I understand a theorem when it seems obvious to me. Of course, sometimes the definition of "obvious" needs to be relaxed a bit... but at the very least I want the proof method to seem obvious.
Jul
11
comment Radical Solvable quintic polynomial.
I think the simplest approach would be to consider the equivalent (I think) question about the Galois group: show that a subgroup of $S_5$ is solvable iff its order is less than $60$.
Jul
10
comment Why isn't the Cantor Set contradictory?
The fact that (a) and (b) seem to be contradictory is part of the point of constructing the Cantor set.
Jul
10
comment “Simple” beautiful math proof
Strictly speaking, what you have is a proof that there is no rational number whose square is $2$. The evidence that it's reasonable to nevertheless talk about something called $\sqrt 2$ has to come from elsewhere.
Jul
10
comment Finding a series of common multiples given arbitrary numbers
Are you interested in enumerating all common multiples $m$ of a set of numbers with $m<M$, with $M$ some arbitrary upper bound?
Jul
9
comment Does a discrete time signal have a formula or one definite equation?
What do you mean by "heart rate signal"? A sequence of real numbers?
Jul
9
comment How to interpolate and obtain this graph?
@Chinny84 It's just that the only real information to go on from that graph is that the OP wants a concave graph, and a quadratic is the simplest example I can think of that can do that.
Jul
9
comment How to interpolate and obtain this graph?
A simple quadratic interpolation should produce that sort of curve, shouldn't it?
Jul
7
comment Zermelo–Fraenkel set theory the natural numbers defines $1$ as $1 = \{\{\}\}$ but this does not seem right
I've never seen the point of view that formalization is essentially just expressing something in another language/symbolism, that's an interesting way of looking at it.
Jul
7
comment How do you compute the inverse of the following permutation?
Are you sure you can't compute the inverse? Do you understand the definition of "inverse"?
Jul
6
comment Possible Fields?
@user161978 "Cauchy sequence" doesn't mean anything in the context of an arbitrary field! What is the metric? (There is in fact one standard answer to this question, which is to require an absolute value and consider the induced metric).
Jul
6
comment Need help understanding a paragraph from a book
@Fermat True, but if you give the OP the impression that something called "series" are required to understand this, they'll google that, see the calculus stuff, and potentially get scared off (given their request to explain it using high-school math).
Jul
6
comment Need help understanding a paragraph from a book
This is a finite sum, no series are required.
Jul
6
comment How many times can you round a number?
This doesn't answer the question. The question is about how many iterations it takes for a particular rounding algorithm to terminate.
Jul
5
comment Bijection from $\mathbb{R}^n$ to $\mathbb{R}$ that preserves lexicographic order?
This is definitely not abstract algebra. I'd be tempted to tag it as topology, but I'm not sure.
Jul
5
comment Why is this proof of $\mathbb{N}\times\mathbb{N}$ being countable not formal?
Rigor is not a rigorously defined notion. It's a spectrum.
Jul
5
comment How to distinguish walking on a sphere or on a torus?
To be more systematic, get a partner and a rope eash and walk out from the same starting point at right angles to one another, always in a straight line. If you're on a torus, both of you will return home, but one of you won't be able to contract the rope.
Jul
5
comment Additive non-abelian group?
@user139981 Yes, typically denoted by $x^n$ in the general case.
Jul
4
comment Meaning of the characteristic polynomial of a matroid
I'm not sure your interpretation of the characteristic polynomial of a matrix, in the last paragraph, is really all that profound. What do you mean by "how close"?