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Wizact
  • Member for 5 years
  • Last seen this week
  • Groningen, Nederland
7 votes

Why does every oscillating sequence diverge?

4 votes
Accepted

How to transform $z$ into $\hat z$

4 votes

Proving $f(x) =g(x)$ for all $x$

4 votes
Accepted

Proving every Cauchy sequence is convergent. Does the following proof work?

4 votes
Accepted

Finding basis of subspace of $\mathbb{R}^4$ such that $x_1 + x_2 + x_3 + x_4 = 1$

3 votes
Accepted

I can't understand why characteristic functions are measurable

3 votes
Accepted

Any central force implies conservation of angular momentum

3 votes
Accepted

Why does the trace show up in such expressions?

3 votes
Accepted

$\mathbb{Q}$ is closed in $\mathbb{R}$?

3 votes

Kernel of a linear transformation between vector spaces of different dimensions

2 votes
Accepted

Proving Continuity by Showing Open Pre-image

2 votes
Accepted

Any guide please, operator theory

2 votes
Accepted

What does the notation $\left<\frac{\partial\Phi}{\partial\theta},\frac{\partial\Phi}{\partial\theta}\right>$ mean in differential geometry?

2 votes

Determinants of upper-left submatrices

2 votes
Accepted

Using the diameter of a set in the proof that a bounded and closed set is compact (Heine-Borel in Rn)

2 votes
Accepted

Proving that an nth degree polynomial eventually strictly increases / decreases.

2 votes

Real Analysis Cauchy sequences

2 votes
Accepted

On the proof that $x^2+y^2-z^2=1$ is a topological manifold

2 votes

Show that $T(O)$ is not open in $Y$

2 votes

Are solutions of linear Equations vectors?

2 votes
Accepted

Confusion in Picard's Method of Successive Approximation

2 votes

Solving Cauchy problem using implicit function

2 votes
Accepted

Rotation of a matrix at an angle

2 votes

Finding the null space, problem with this exercise.

1 vote
Accepted

Proving linearity of the differential operator $a_n(x)D^n+a_{n-1}(x)D^{n-1}+\ldots+a_1(x)D+a_0(x)$.

1 vote

Equality of equivalence relations that partition the same set.

1 vote
Accepted

Can you give me a good explanation and an example of a topological linear space?

1 vote

Prove, that $\vec{\phi }(t)=e^{\lambda_0t} \cdot \vec{x}_0 $ is a solution to the system $X'=AX$

1 vote

Evaluating definite integrals via contours

1 vote
Accepted

Given a point $p\in M$ and a tangent vector $v \in T_p M$, is there a smooth vector field $X$ on $M$ such that $X(p)=v$?