DLV's user avatar
DLV's user avatar
DLV's user avatar
DLV
  • Member for 9 years, 10 months
  • Last seen more than 1 year ago
20 votes
5 answers
7k views

Substituting for Taylor series

17 votes
6 answers
7k views

Arithmetic mean. Why does it work?

11 votes
2 answers
179 views

When is $\sqrt{a^2}=\pm a$ and when is $\sqrt{a^2}=a$?

6 votes
1 answer
18k views

Delta function in spherical coordinates. Does my professor have a mistake?

5 votes
2 answers
26k views

The existence of the laplace transform

4 votes
2 answers
522 views

Why can the equality sign be used for Fourier series expansion of a discontinuous function?

4 votes
1 answer
181 views

Integrating via partial fractions

4 votes
2 answers
1k views

how to prove gradients vectors are the same in polar and cartesian coordinates.

4 votes
2 answers
28k views

Showing Bessel function of first kind (order 1/2) is $J_{1/2}(x)=\sqrt{\frac{2}{\pi x}}\sin(x)$

4 votes
1 answer
1k views

Noether's theorem and lie groups. A question related to the meaning of a lie group.

4 votes
1 answer
158 views

Is this Cayley Diagram contradictory?

4 votes
1 answer
22k views

Finding the autocorrelation of a sine wave.

3 votes
2 answers
270 views

Is $|x+y|\geq\big||x|-|y|\big|$ true?

3 votes
1 answer
67 views

I dont see how this algebraic manipulation is valid (trig functions)

3 votes
1 answer
1k views

Find the min and max distance from origin of the curve $\vert z+\frac{1}{z}\vert=a$

2 votes
1 answer
822 views

Clairauts "equality of mixed partial derivatives" theorem (interpretation)

2 votes
1 answer
212 views

How to find a sensible approximation of $R\dot{\theta}^2+\ddot{\theta}(R\theta-l)+g\cos\theta=0$

2 votes
1 answer
350 views

Does the Discrete Fourier Transform assume a periodic signal, or one that dies off?

2 votes
0 answers
74 views

basic question of differential geometry.

2 votes
1 answer
301 views

Confusion about partial and total derivatives.

2 votes
1 answer
110 views

How can eigenvectors of a Hermitian matrix be entangled?

2 votes
2 answers
261 views

Wrong interpretation of the indefinite integral

2 votes
2 answers
899 views

How can vectors with different units (position, speed, ...) "share" the same space?

2 votes
1 answer
470 views

Why aren't exact differential equations considered PDE?

2 votes
2 answers
109 views

Proving arithmetical properties for non-natural numbers

2 votes
2 answers
3k views

Why does the cross product follow the right hand rule?

1 vote
1 answer
122 views

Solve system of diff equations using laplace transform and evaluate x(1)

1 vote
1 answer
371 views

Existence of the laplace transform $sin(8t^{3})$

1 vote
2 answers
856 views

Solving physics problems as a regular math problem. Why can we ignore units altogether?

1 vote
3 answers
211 views

Question on the definition of vector spaces.