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Revoltechs
  • Member for 6 years, 6 months
  • Last seen more than 1 year ago
3 votes
5 answers
787 views

Prove that for any integer $a$, $9\nmid(a^2-3)$.

2 votes
0 answers
102 views

Vector equation of line containing point and perpendicular to plane [duplicate]

2 votes
2 answers
104 views

If $p>5$ is prime and $2p+1$ is prime, then $4p+1$ is composite.

1 vote
2 answers
73 views

Does the sequence $x_{n+1}=x_n+x_n^2$ converge to $0$ whenever $-1\lt x_0\lt0$?

1 vote
0 answers
22 views

Find functions $f(n)$ and $g(n)$ such that $f(n)\in\Omega(g(n))\setminus\Theta(g(n))$, but $\lim_{n\to\infty}$ does not exist.

1 vote
1 answer
26 views

Proof that $\forall k\in\mathbb Z^+$, $\lfloor\log_2(2k+1)\rfloor=\lfloor\log_2(2k)\rfloor$

1 vote
1 answer
14 views

Prove: $\forall a\in\mathbb R$, $\max\{y=x(a-x):x\}=\frac{a}{2}$

1 vote
1 answer
61 views

Prove that if $a\nmid b$, $ax^3+bx+(b+a)=0$ has no natural number solutions

1 vote
1 answer
117 views

$\forall n\in\mathbb N$, let $A_n=\{x\in\mathbb R\mid n-1\lt x\lt n\}$. Prove that $\displaystyle\bigcup_{n\in\mathbb N}A_n=(\mathbb R^+-\mathbb N)$.

1 vote
1 answer
60 views

$\forall n\in\mathbb N$, let $A_n=\{k\in\mathbb N\mid k\geq n\}$. Prove that $\displaystyle\bigcap_{k\in\mathbb N}A_k=\emptyset$.

1 vote
0 answers
87 views

Prove that there is a bijection between $\mathbb R^*$ and the set of all equivalence classes for an equivalence relation.

1 vote
1 answer
53 views

Prove that $(1+x)^n>1+nx$ for all integers $n\geq2$, where $x>-1$ and $x\neq0$.

1 vote
2 answers
224 views

What does $\mathbb{R}_0^+$ mean?

0 votes
1 answer
115 views

Prove that $\sum_{i=1}^n\Theta(i)=\Theta(n^2)$.

0 votes
0 answers
48 views

Local max and min of $e^{−x} − e^{−4x}$

0 votes
2 answers
705 views

Prove that two subspaces of a vector space intersect only at 0

0 votes
1 answer
21 views

What is the angle between a $A_{3x3}$ with $Rank(A)=2$ and $A^T$

0 votes
0 answers
39 views

Approximate my grade in a class, based on knowledge of the curve that was used

0 votes
1 answer
24 views

Prove that $3^{2^n}=o(2^{3^n})$