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Mark Fantini
  • Member for 8 years, 11 months
  • Last seen this week
  • Brazil
5 votes
4 answers
1k views

Prove that if the altitude and median of a triangle form equal angles with sides then the triangle is right.

4 votes
1 answer
157 views

Mixed partial derivatives are different

4 votes
1 answer
795 views

Energy associated with PDE

4 votes
1 answer
834 views

Stone–Čech compactification: clarification of definition

3 votes
4 answers
1k views

Quick way to solve the system $\displaystyle \left( \frac{3}{2} \right)^{x-y} - \left( \frac{2}{3} \right)^{x-y} = \frac{65}{36}$, $xy-x+y=118$.

2 votes
2 answers
229 views

Upper bound of a set (equivalence problem)

2 votes
1 answer
78 views

Integrating the Fourier Transform

2 votes
2 answers
1k views

Proving $ \frac{x^3y^2}{x^4+y^4}$ is continuous. [duplicate]

2 votes
1 answer
533 views

Hadamard's Lemma in multidimensional real analysis

1 vote
1 answer
249 views

Transforming from cartesian to cylindrical

1 vote
1 answer
102 views

First countable spaces, enumerable neighborhood base system

1 vote
1 answer
155 views

Geometrically distributed random variable

1 vote
2 answers
1k views

Countable subsets are disconnected

1 vote
1 answer
65 views

Volume of revolution of the area between $\sec(x-1)$ and $\ln(x)$ for $1 \leq x \leq 2$

1 vote
1 answer
39 views

Showing a sequence is a Cauchy sequence in $\operatorname{End}(\Bbb R^n)$

0 votes
1 answer
184 views

Given sides and a bisection, find angles in a triangle

0 votes
1 answer
127 views

Resources for solving Euclidean geometry problems using symmetries