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  • Member for 7 years, 7 months
  • Last seen more than 7 years ago
14 votes
Accepted

$\liminf$ of a sequence of functions

13 votes
Accepted

Existence of a non-constant entire function

12 votes
Accepted

Why is Hawaiian earring not semilocally simply connected?

11 votes

Issue with Spivak's Solution

11 votes

Prove that an infinite sigma algebra contains an infinite sequence of disjoint sets and is uncountable

10 votes
Accepted

Problems with the proof that $\ell^p$ is complete

10 votes
Accepted

Summing up series which is similar to Taylor expansion

8 votes
Accepted

If $\log_{12}54=a$ then $ \log_{6}12=?$

8 votes
Accepted

Solve for $n$, with factorial.

8 votes
Accepted

Convergence of a sequence of functions and their inverses

7 votes
Accepted

How to prove, that solution of system $Ax = b$ exists only if there is no solution of $A^T y = 0$ and $b^T y = 1$?

7 votes
Accepted

Simplify the sum $ \sum_{k=1}^{\infty} (\frac{1}{2})^kk $

6 votes
Accepted

Prove that the set $X+Y$ is closed

6 votes
Accepted

Let A be a measurable set in R. Let B be all of it's densed points. is B necessarily open?

6 votes
Accepted

Function holomorphic except for real line and continuous everywhere is entire

6 votes
Accepted

Every affine variety in $\mathbb A^n$ consisting of finitely many points can be written as the zero locus of $n$ polynomials

6 votes
Accepted

Convergence in inner product space

6 votes
Accepted

Show that $Y^2 + X^2(X+1)^2$ is irreducible over $\mathbf R$

6 votes
Accepted

How prove this matrix $A$ similar with $A^T$

5 votes

$E$ measurable set and $m(E\cap I)\le \frac{1}{2}m(I)$ for any open interval, prove $m(E) =0$

5 votes

How do I find the error of nth iteration in Newton's Raphson's method without knowing the exact root

5 votes
Accepted

Prove that there is an infinite simple path in a Graph

5 votes
Accepted

Embedding $L^2[0,1]$ into any Hilbert space?

5 votes
Accepted

Dense subset in sequence space

5 votes
Accepted

Solve the Differential Equation $\frac{dy}{dx}=2+\sqrt{y-2x+3}$

4 votes
Accepted

Solve the following equation for x and y:

4 votes
Accepted

Inner Product on $\mathbb{R}$ and on $\mathbb{C}$

4 votes

$\mathbb{R}$ with the lower limit topology is not second-countable

4 votes
Accepted

Linear operator norm

4 votes
Accepted

finding $\int\frac{1}{(t^2+25)^2} dt$ without trig substitution

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