Mathematics Stack Exchange
Mathematics Stack Exchange

Questions tagged [solution-verification]

For posts looking for feedback or verification of a proposed solution. "Is my proof correct?" is too broad or missing context. Instead, the question must identify precisely which step in the proof is in doubt, and why so. This should not be the only tag for a question, and should not be used to circumvent site policies regarding duplicate questions.

This tag should be used when you have a proposed solution to a problem and have specific concerns or doubts about the validity of that solution. A question with this tag should include an explanation for why the argument presented is not convincing enough. Further discussion on using this tag can be found in the Mathematics Meta questions (1) and (2).

Answers to questions tagged look first and foremost to check that the solution is right, and to comment upon the approach taken by the author of the question. If the proposed solution is wrong, a good answer would explain where or how mistakes were made, and possibly give or sketch a correct solution instead.

If the proposed solution is correct, an answer would ideally provide further evidence to back the answerer's opinion. These could include a clearer rewriting of the given argument, alternative arguments, generalizations of the proven result, or careful consideration of unexpected subtle points. Users looking to write answers can find further discussion in this Mathematics Meta post.

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Difference between Verify, Prove and Argue

I have seen all these three terms used quite interchangeably. I've referred to some Logic books, and I couldn't find any clear and sharp distinction between these terms. I found this, but it doesn't say much. In terms of English words, OK, I…
Giorgi Tsiklauri
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Is the following a valid proof in number theory?

Prove the following using fundamental definitions. Suppose $a$, $b$, and $c$ are positive integers such that $a|b$ and $a|c$. Then for any integer $k$, $ka + 3b ≡ c \mod a)$ What I've done: "We need to show $ka + 3b ≡ c(mod a)$. So by the…
Maru
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Given that $a+b+c=0$, show that $2(a^4+b^4+c^4)$ is a perfect square

Given that $a+b+c=0$. Show that: $2(a^4+b^4+c^4)$ is a perfect square MY ATTEMPTS: I found that when $a+b+c=0$, $a^3+b^3+c^3=3abc$ So I did: $(a^3+b^3+c^3)(a+b+c)$ -- $a^4+b^4+c^4=-(a^3c+a^3b+ab^3+b^3c+c^3a+c^3b)$ And then I tried to substitute…
Port0
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Prove $\frac{2k+2}{2k+3}>\frac{2k}{2k+1}, k\in\mathbb N$

Prove $\frac{2k+2}{2k+3}>\frac{2k}{2k+1}, k\in\mathbb N$ The book I am using asserts a non-trivial way of proving this inequality, but I cannot see why this cannot be proven by rearranging the statement equally as…
jamie
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Proof Verification Language

Sometimes I write proofs, but I have no one to ask if it indeed makes sense. I was wondering if there is some type of language where tell it the tools I have to prove this statement, the statement and my proof, and it can tell me if the proof is…
cuppajoeman
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If $x+y$ and $y+z$ are even, prove $x+z$ is even

I'm stuck on a practice problem for an upcoming midterm. Can someone tell me if I'm starting off on the right foot here? Q: $x,y,z \in \mathbb{Z}$. $x + y$ and $y + z$ are even. Prove that $x + z$ is even. I thought it would be easier to prove…
nicons
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How to Prove It A Structured Approach 3.2 Exercise 8: Did I prove it?

Suppose that a and b are nonzero real numbers. Prove that if $a < \frac{1}{a} < b < \frac{1}{b}$ then $a < -1$. Here's my attempt: Suppose that $a < \frac{1}{a} < b < \frac{1}{b}$, and that $a > 0$. Multiplying the inequality by $a$, we get $0 <…
A Name
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Prove or Disprove: There exists positive integers $x, y, z$, such that $x^8-y^5=z^3$

$x^8-y^5=z^3$ I believe it is some form of a Diophantine equation but since each variable is to a different power, I am unable to solve it.
user748161
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How to prove that $ab=a^2+4ab+4b^2$ is not true?

Basically the title, this problem is from statistics so $a$ and $b$ are natural numbers including 0.
Martynas Krupskis
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Is this proof of: $\exists a,b \notin \mathbb Q : a^b \in \mathbb Q$ valid?

Statement: $\exists a,b \notin \Bbb Q : a^b \in \Bbb Q$ Proof: Set $\lambda=\sqrt 2^\sqrt2$ if $\lambda\in\Bbb Q$, then $\sqrt 2^\sqrt2 \in\Bbb Q,\space a=b=\sqrt 2 \notin \Bbb Q$. if $\lambda\notin\Bbb Q$, then…
Tony
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Mass of Hemisphere

Could someone check my work please? The question said to write an integral in spherical coordinates and evaluate it to find the mass of the hemisphere: $x^2+y^2+z^2\leq4; z\geq0$ if the density $\rho(x,y,z)$ is equal to $2z$. My work: $m=…
Gabriel
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Find the solutions of an equation with arctan?

I have to show that $1$ and $\frac{-1}{\sqrt{3}}$ are (maybe not) solutions of the following equation: $arctan(x)+arctan(x\sqrt{3})= \frac{7\pi}{12}$. How can I do that ? Thank you in advance
vev78
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Verify my answer: show a bijection from (0,1) into [0,1]

Could someone verify my answer? Am i correct? Question: Show a bijection from $[0,1]$ (closed) into $(0,1)$ (open) Answer: Define a sequence $X = \{x_{n}\}_{x\in\mathbb{N}}$ by $ x_{n} = \frac{1}{(2n-1)}$ such that $X \subset [0,1]$ and a sequence…
Guilherme Duarte
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Does my Proof to 3.3(b) Work? (From Introduction to Set Theory: Third Edition)

: I'm currently working through the book "Introduction to Set Theory: Third Edition" by Hrbacek and Jech and I came up with the following proof to $3.3(b)$ above (p12 in the book): Suppose for a contradiction that there exists a set $A$ such that…
1231231
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Is my proof correct? Infinite rational numbers

Question Prove that between any two points a and b ($a\not=b$) on the x-axis there are infinitely many rational points. My Proof Lemma 1. Between any 2 rational numbers there exist infinite rational numbers. Let $b\ge a$ multiply $a$ and $b$ by…
Cruz Caine
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