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Zuy's user avatar
Zuy's user avatar
Zuy
  • Member for 4 years, 4 months
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18 votes
Accepted

What is the logical flaw in this reasoning? Abusing $T \equiv T \vee F$.

10 votes

Algebraic proof that $\sum\limits_{k=0}^{n} {n \choose k}\cdot \frac{(-1)^k}{(k+1)(k+2)} = \frac{1}{n+2}$

10 votes
Accepted

Negative Numbers in Math & Physics

9 votes
Accepted

Show that, if $n$ is even, then the polynomial $p(x) =x^n + x^{(n-1)}+...+x+1$ does not have real roots.

8 votes
Accepted

Does $f(a,b)$ being directly proportional to $a$ and $b$ separately imply that $f(a,b)$ is directly proportional to $ab?$

7 votes
Accepted

The empty set fails to satisfy only one of the axioms of vector spaces. Which one? ("Linear Algebra Done Right" by Sheldon Axler.)

6 votes

Find the algebraic dimension of space of matrices

6 votes

If a bounded sequence $\{a_n\}$ has no convergent subsequence, is it true that $|a_n−a_m|≥ \epsilon$ for some $\epsilon$ for all $n , m$

5 votes
Accepted

Vitali set proof: Why is $1 \leq \sum_{k \in \mathbb{N}}m(\mathcal{N}_k) \leq 3$ impossible?

4 votes
Accepted

$ \sum_{x=1}^n {{n-1} \choose {x-1}} {N \choose x} = {{N+n-1}\choose n}$

4 votes

Understanding how nth root can equal 1

4 votes

During certain sequences of coin flips, why does HHHT have a greater chance than HHHH?

4 votes

The Cartesian Product of two metric spaces and sequences that converge

3 votes

Equivalence relation criteria

3 votes

Given the sequence of real numbers with the restrictions $0<x_n<1$ and $(1-x_n)x_{n+1}>\frac{1}{4}$, show that $\lim_{n\to\infty} x_n=\frac{1}{2}$

3 votes
Accepted

Showing $f(x) = xe^{-nx^2}$ is a bounded function

3 votes

Find $\log_e3 - \frac{\log_e9}{2^2} + \frac{\log_e27}{3^2} - \frac{\log_e81}{4^2} + ...$

3 votes

Differentiability of $f(|x|)$

3 votes
Accepted

Prime Counting on Intervals - is this deduction valid?

3 votes

Bell numbers (number of partitions of set of cardinality n) recurrence relation proof

3 votes
Accepted

An identity on binomial coefficients without using explicit formulas

3 votes
Accepted

Is my proof of the $|a||b|=|ab|$ property correct?

3 votes

Equations involving logarithms without calculator

3 votes
Accepted

Is this conjecture related to Euler's totient function known?

3 votes
Accepted

An impossible congruence

3 votes
Accepted

finding the exact value of $\sin 195^\circ$

2 votes
Accepted

Why the difference of two measures is a signed measure?

2 votes

Is $x^3$ really an increasing function for all intervals?

2 votes

How do I calculate the following sum $\sum_{i=0}^{n+1} \dbinom{n+1-i}{i} $

2 votes

Potential misunderstanding in reading Set Theory by Hrbacek

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