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Alejandro Tolcachier's user avatar
Alejandro Tolcachier's user avatar
Alejandro Tolcachier's user avatar
Alejandro Tolcachier
  • Member for 5 years, 5 months
  • Last seen this week
6 votes

homeomorphisms mapping interiors to interiors and boundaries to boundaries

5 votes
Accepted

Does there exist an analytic function whose real part is $x^2+y^2$?

4 votes

Injective Lie Group Homomorphism is Immersion?

3 votes
Accepted

Homomorphism from a ring with unity to a integral domain maps unity to unity?

3 votes
Accepted

Two functions differing at finitely many points have the same Riemann integral.

3 votes
Accepted

Inclusion between diagonalizable , unitary, normal and hermitian?

3 votes
Accepted

If $\tan\theta =\cos2\alpha\tan\phi$ then prove that $\tan(\phi-\theta)=\frac{\tan^2\alpha\sin2\phi}{1+\tan^2\alpha\cos2\phi}$

3 votes

Find Analytic Function

2 votes

Is this correct : $x,y,z,t$ natural numbers If : $x\mid y+z+t$ and $x\mid y$ $\implies x\mid z+t $?

2 votes
Accepted

Smoothness is local

2 votes
Accepted

$F$-related vector fields, $Y$ complete implies $X$ complete?

2 votes
Accepted

Confirming eigenvectors of a matrix

1 vote

Group $G$ of order $24$ that is either $S_4$ or $G/Z(G)$ is $A_4$.

1 vote
Accepted

Ricci and scalar curvature

1 vote
Accepted

Injective and quasi injective modules

1 vote
Accepted

The center of a direct product of groups and Abelian groups

1 vote
Accepted

Evaluate a contour integral with Taylor coefficients

1 vote

Two Lie Group homomorphisms are equal if their induced Lie algebra homomorphisms are equal and $G$ is connected

1 vote

Keyhole contour in complex analysis

1 vote

prove the two following infinite unions/intersections

1 vote

Prove by limit definition $\lim _{x\to \infty }\left(\frac{-7x^2+9x}{4x^2+8}\right)=\frac{-7}{4}$

1 vote

An obscure explanation in Conway's Complex analysis

1 vote
Accepted

$x \mapsto \frac{1}{x}$ if $x \neq0$, $x \mapsto 0 $ if $x =0$

1 vote

Find all analytical functions with this property

1 vote
Accepted

If $\alpha\ne0$ and $\beta\ne0$, show that $E_{ij}(\alpha)$ and $E_{mn}(\beta)$ commute iff $i\ne n$ and $j\ne m$

1 vote
Accepted

Elementary inequality involving modulus

0 votes

Proof Question involving subspaces in Linear Algebra

0 votes
Accepted

Is $T$ a nonlinear map?

0 votes

Determine the coordinates of the vector $(4,3,2,1)$ in the basis $\{(1,0,0,0),(1,1,0,0),(1,1,1,0),(1,1,1,1)\}$

0 votes
Accepted

$\Gamma(z)\Gamma(1-z)=\pi \csc \pi z$. Justify the correct manipulate of products