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Irddo's user avatar
Irddo's user avatar
Irddo
  • Member for 10 years, 10 months
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6 votes

Good book to study ODEs through geometric ideas

4 votes

Complex analysis textbook advise

3 votes

Groups - Proof that $(ab)^{-1} = b^{-1}a^{-1}$

3 votes

Divisibility by a prime number p.

3 votes
Accepted

Functionnal analysis: Why $\langle AAx,x\rangle\underset{(*)}{\leq} (\|A\|+m)\langle Ax,x\rangle-\|A\|m ?$

3 votes
Accepted

Example of an $H^{-1}$ function that isn't $L^2$

3 votes

How do you find $y'$ for $x^y = y^x$?

3 votes
Accepted

Show that $\max{\{|a|+|b|,|c|+|d|\}} \leq \max{\{|a|,|c|\}}+\max{\{|b|,|d|\}}.$

2 votes
Accepted

Applaying equivalence of norms to show a sequence is a Cauchy sequence

2 votes

where is the singularity of this function?

2 votes

A determinant made of $n \times n$ determinants.

2 votes

What is a dual space?

2 votes
Accepted

Relation of gamma function to a factorial mimic function

2 votes

Puiseux Series?

2 votes

Let $(x_n)$ be a sequence that converges to a number x. Show that $(s_n)$ converges to x as well.

1 vote

Prove that $int(A)=A\setminus bd(A)$

1 vote

Multivariable Calculus: Intersection of surface and planes

1 vote

Vectors, dot product

1 vote

Fractions and Largest Common Multiple, Algebra, Numerator and Denominator Identical Numbers?

1 vote
Accepted

Fourier transform of $f'(t)$

1 vote

What equation represents the line that passes through $(–6, 7)$ and $(–3, 6)$?

1 vote

Why is this function uniformly continuous?

1 vote
Accepted

Why does a differential form represent a vector field?

1 vote
Accepted

Closedness of a complex $1$-form defined by homogeneous functions

1 vote

How to prove the existence of vectors?

1 vote

Average Value of a Surface

1 vote
Accepted

Would this be a valid proof for $\left| x + y \right| \geq \left| x \right| - \left| y \right|$

1 vote

Exterior derivative of a coordinate function

1 vote

Questions about definitions in Surface Theory

1 vote
Accepted

First variation formula $ \int_M div _M Y = -\int_M \langle H , Y \rangle $