Skip to main content
AspiringMat's user avatar
AspiringMat's user avatar
AspiringMat's user avatar
AspiringMat
  • Member for 8 years, 6 months
  • Last seen this week
25 votes
3 answers
20k views

Do inequalities hold under differentiation?

12 votes
2 answers
748 views

What is the expected number of infected people?

9 votes
1 answer
352 views

Proving $n$ subsets $A_1, ..., A_n$ of size $\geq 2$ must pairwise intersect.

7 votes
2 answers
238 views

Prove ${2n \choose n+i} \geq e^{-8 i^2/n} {2n \choose n}$

6 votes
1 answer
259 views

Minimum of $\prod_{1\leq i \leq n} (1-p_i) \left[ \sum_{i=1}^n \frac{p_i}{1-p_i} + \sum_{i=1}^n \sum_{j=i+1}^n \frac{p_i p_j}{(1-p_i)(1-p_j)} \right]$

6 votes
2 answers
4k views

Is $XX^T$ invertible?

6 votes
1 answer
3k views

Find the area of the part of the paraboloid $z = x^2 + y^2$ that lies under the plane $z=4-x$

5 votes
2 answers
298 views

Intermediate Value theorem inequality problem

4 votes
5 answers
774 views

If $\lim_{n \rightarrow \infty} (a_{n+1}-\frac{a_n}{2})=0$ then show $a_n$ converges to $0$. [duplicate]

4 votes
2 answers
105 views

Let $f,g[0,1]\rightarrow \mathbb{R}$ be continuous. $\exists x_n$ $\forall n( g(x_n)=f(x_{n+1}))$. Prove $\exists w\in[0,1],f(w)=g(w)$

4 votes
1 answer
311 views

Existence of $k$ permutations whose composition is the identity.

4 votes
6 answers
478 views

Number of bit strings of length $n$ with no $k_1+1$ consecutive 0s and no $k_2+1$ consecutive 1s.

4 votes
2 answers
1k views

Can you apply the fundamental theorem of calculus with the variable inside the integrand?

4 votes
2 answers
6k views

Suppose that 21 girls and 21 boys enter a math contest, Show that there is a question that was solved by at least three girls and at least three boys.

4 votes
1 answer
74 views

A $a\times b \times c$ cube formed by small $1^3$ cubes. If a laser beam travels along the diagonal of the cube, how many small cubes does it cross?

4 votes
1 answer
261 views

What is the expected total number of topological sorts in a Directed a cyclic graph with $n$ vertices?

4 votes
0 answers
49 views

Inverting Linear System of Inequalities

3 votes
1 answer
446 views

How to prove LP integral solution when total unimodularity fails?

3 votes
2 answers
428 views

Prove there is only one subgroup of order $p$

3 votes
3 answers
7k views

How to solve $AX=XB$ for $X$ Matrix?

3 votes
1 answer
174 views

If $\Phi:G \rightarrow G$ is a group homomorphism, $\Phi(x)=ax^3a$ then what is $Ker \Phi, Im(\Phi)$

3 votes
0 answers
74 views

Maximum number of umbrellas that can be added in a one kilometer beach?

3 votes
2 answers
431 views

What is the fastest way to calculate the $n$th coefficient of a generating function Modulo a prime $p$

3 votes
1 answer
34 views

Getting negative the correct answer in $\iint_R e^{x+y}dA, R=\{(x,y)\quad |\quad|x|+|y|\leq 1\}$

2 votes
2 answers
3k views

Closed line integral of conservative field not zero?

2 votes
0 answers
86 views

Find subset of size $k$ such that it maximizes the metric distance of the elements.

2 votes
1 answer
47 views

Proof verification: Let $S=\{2^{-n}:n\in \mathbb{N}\}$ and $f:\mathbb{N}\rightarrow S$ is injective. Show $\lim_{n\rightarrow \infty}f(n)=0$

2 votes
3 answers
2k views

Prove a one sided inverse matrix $B_{m\times m}$ of $A_{m\times m}$ is two sided inverse.

2 votes
1 answer
555 views

Villager Logic Puzzle Alternative Answer

2 votes
1 answer
544 views

Position function of a point moving in a circle with velocity $v_0$ and initial position $r_0$ with reflection.