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Nick The Dick
  • Member for 2 years, 8 months
  • Last seen more than a month ago
55 votes
7 answers
8k views

Why the real and imaginary parts of a complex analytic function are not independent?

4 votes
1 answer
83 views

"Determine all functions $\Bbb{Z}\to\Bbb{Z}$ such that $f(2a)+2f(b)=f(f(a+b))$"

3 votes
1 answer
43 views

Intuition for why we can apply complex analysis to solving 2D cases in applied science problems

2 votes
2 answers
160 views

Why is the vector $(u_x, u_y, - 1)$ normal to the surface $u=u(x, y) $?

2 votes
0 answers
28 views

Theorem weakening/strengthening confusion

2 votes
2 answers
152 views

Derivative of $\log(r)$ with respect to $x$

2 votes
1 answer
321 views

Help me understand a proof of Rouche's theorem

1 vote
3 answers
3k views

Solving auxiliary equations in Charpit's method. Non-linear first-order ODE.

1 vote
0 answers
36 views

Solve $pq^2=ax+by$ - a nonlinear first-order pde

1 vote
1 answer
169 views

Unclear first step in proof of the Schwarz Integral Formula.

1 vote
1 answer
53 views

Finding the residue of $\frac{1}{ \sqrt{z^2+z+1}}$

1 vote
1 answer
23 views

Proof that if a sequence of random variables converges weakly to a constant, then it converges to it in probability

1 vote
1 answer
343 views

Defining stream function and velocity potential function

1 vote
0 answers
18 views

Confusion about posterior distribution dependence on priors in this example

1 vote
2 answers
720 views

Intuitive meaning of Neumann boundary condition

1 vote
1 answer
104 views

Surjectivity of operator $(\lambda I-A)x$, where A is a linear operator on a Hilbert space $X$, for non-real $\lambda$

1 vote
1 answer
41 views

Fourier cosine series coefficients

1 vote
1 answer
221 views

How to compute confidence interval for variance with unknown mean from a normal $(a,\sigma ^2)$ sample?

0 votes
1 answer
27 views

Unsure of a proof shorcut in a simple chasing the angle problem

0 votes
0 answers
12 views

Numerical solution's evolution's dependance on timestep and the absolute time passed.

0 votes
1 answer
34 views

Inverse operator in the space of infinite bounded sequences $l_2$

0 votes
0 answers
32 views

Understanding the proof of the Compactness principle

0 votes
0 answers
23 views

Cumulative distribution function of sample average of size 4

0 votes
0 answers
17 views

Double integral over a paremeterised and a general surface

0 votes
1 answer
63 views

Qualitative understanding of Fisher Information

0 votes
0 answers
29 views

If space projects onto a sphere inside our eye, why do we see flat photographs as normal-looking?

0 votes
2 answers
48 views

Confusion about how a dual space element is also a mapping.

0 votes
0 answers
47 views

Proof of Chebyshev's inequality question

0 votes
2 answers
253 views

Reducing to the canonical form of a linear pde with constant coefficients in 4 dimensions

0 votes
1 answer
60 views

Convert $-2xy+2zx-x^2$ into a sum of three squares of expressions of $x,y$ and $z$