
Please post any and all homework or other textbookstyle problems in one of the Homework & Coursework Questions...

Feb2313 09:25 AM
micromass

1 
30,976 
I've been thinking of a solution, but can't find a one. You have a square of side length 1. You have to draw 2 circles...

Nov1212 05:40 PM
Studiot

2 
1,066 
Hello!
I am a bit confused about how I can use covector fields on a differentiable manifold.
John M. Lee writes...

Nov1212 10:10 AM
Vargo

6 
1,659 
Hello,
can anyone suggest a geometric interpretation of the metric tensor?
I am also interested to know how we could...

Nov1212 09:17 AM
lavinia

12 
2,283 
Suppose that points x and y are given in Euclidean space. Point x is displaced to point x1 by
x1=x+a(xy)
Given...

Nov1212 07:27 AM
tinytim

3 
1,052 
Hi, All:
I need some help with some "technology" on differential forms, please:
1)Im trying to understand...

Nov1212 07:26 AM
quasar987

1 
925 
Hello everyone,
I'm studying basic graph theory, and my instructor gives me these statements to translate into...

Nov1112 07:35 PM
Simon Bridge

1 
922 
Say I have a function F(x,y)=(f(x),g(y)), F:X×Y→X'×Y'. Is there a theorem that says if f:X→X' and g:Y→Y' are...

Nov912 04:15 PM
sammycaps

10 
1,561 
I am currently reading a paper discussing the convexity of the image of moment maps for loop groups. In particular, if...

Nov912 02:32 PM
Vargo

3 
1,101 
So I'm having a little trouble with the part of Van Kampen's theorem my professor presented to us. He called this the...

Nov912 08:36 AM
sammycaps

4 
1,300 
If the hyperbolic paraboloid z=(x/a)^2  (y/b)^2
is rotated by an angle of π/4 in the +z direction (according to...

Nov812 11:45 AM
BrainHurts

2 
1,223 
I know that physically, they describe relationships whereby, for instance a vector field, for each point in three...

Nov612 03:58 PM
djpailo

5 
1,874 
Does anyone have a good book or reference on computing riemannian connections. I'm looking at Do Carmo and can't find...

Nov612 03:49 PM
lavinia

2 
1,128 
Let S1*(S2*) be the polar cone of the set S1(S2) (http://en.wikipedia.org/wiki/Dual_cone_and_polar_cone).
How can I...

Nov412 06:14 PM
avilaca

5 
1,403 
Hello!
I seem to have a problem with spherical coordinates (they don't like me sadly) and I will try to explain it...

Nov312 10:00 PM
chiro

3 
1,901 
When given a cylinder with radius, height and thickness, how does one go about computing the amount of material used...

Oct3012 09:22 PM
Vargo

1 
864 
All,
I am trying to determine the length of line across 3 dimensions (XYZ). My X&Y are WGS 84 coordinates and my Z...

Oct3012 03:43 PM
entombedtrade

0 
865 
given a compact, orientable, ndim. Riemann manifold, what is a sufficient condition for globally vanishing curvature...

Oct3012 11:36 AM
lavinia

5 
1,340 
Suppose a set of k arbitrary points, x_i, 1<=i<=k, x_i from R^2 are selected from a line. How can it be shown that a...

Oct2912 11:34 AM
Vargo

6 
1,165 
Find the vertices of α(t) = 1  2 cos(t)
I know that to find the vertices we have to set the curvature equal to...

Oct2912 08:02 AM
lavinia

2 
1,020 
Hi
Given is a triangle on points x,y,z in the plane. This triangle has two points a and b on opposite sides (see...

Oct2712 02:00 AM
chiro

7 
1,164 
prove that for any graph G, kappa (G) ≤delta (G).

Oct2712 01:14 AM
Bacle2

3 
1,112 
Can someone please confirm that there is a typo in Nakahara's Geometry, Topology, and Physics, on page 319 (the last...

Oct2612 12:15 PM
mathwonk

3 
1,506 
I shall use Seidel's definition of a Liouville domain; in particular, a Liouville domain is a compact manifold M ...

Oct2412 06:34 AM
quasar987

1 
904 
Does anyone know where I can find an algorithm for the points of intersection of two ellipses existing with arbitrary...

Oct2312 09:34 PM
Norwegian

1 
1,608 
Hi,
I've run into a problem with expanding algebraic functions via Newton polygons. Consider the function:
...

Oct2312 01:13 PM
mathwonk

5 
1,501 
Hello, I've just started learning about asymptotes in school. The questions I have are:
1. To find the vertical...

Oct2212 10:51 AM
mathwonk

1 
778 
I was working on some algebraic topology matters, thinkgs like the connected sum of some surfaces is some other...

Oct2112 12:37 AM
julypraise

5 
1,304 
I had doubts whether to post this here or in in the physics section but I did here because I'm more interested in a...

Oct2012 02:56 PM
Muphrid

91 
9,730 
Let $$M$$ be a surface with Riemannian metric $$g$$. Recall that an orthonormal framing of $$M$$ is an ordered pair of...

Oct2012 07:24 AM
Bacle2

2 
1,036 
Hi,
You guys know of any (software) function which accepts as input an aribtrary algebraic function, then computes...

Oct1812 07:53 PM
mathwonk

6 
1,560 
How do you calculate the Normal vector to an Ellipse.
Radius Vector:
r=rx*i + ry*j + rz*k
Velocity Vector:...

Oct1812 04:48 PM
Philosophaie

15 
3,830 
Let $$(M,g)$$ be an oriented Remannian surface. Then globally $$(M,g)$$ has a canonical area2 form $$\mathrm{d}M$$...

Oct1812 08:34 AM
quasar987

4 
976 
Let $$f:U \to \mathbb{R}^3$$ be a surface, where $$U=\{(u^1,u^2)\in \mathbb{R}^2:u^1<3, u^2<3\}.$$ Consider the...

Oct1812 03:34 AM
semigroups

0 
747 
Hi,
I need to do this for some homework and I don't really understand... could anyone help with the following...

Oct1712 11:14 PM
coalquay404

1 
1,027 
I'm trying to write an algorithm that will create the smallest possible ellipse to encompass any number of points on...

Oct1712 11:40 AM
Physt

4 
1,188 
Take for example, the function:
a_0(z)+a_1(z)w+a_2(z)w^2+a_3(z) w^3+a_4(z)w^4+a_5(z)w^5=0
with the degree of ...

Oct1712 06:28 AM
jackmell

0 
851 
I am having trouble getting a set definition of what constitutes a manifold for example ,
I have the real plane...

Oct1512 11:59 PM
Bacle2

24 
2,148 
I got these people trying to say that you can orientate a solid oblong so that it looks half the length and width with...

Oct1512 10:34 PM
Simon Bridge

3 
1,147 
Suppose I'm given a random function:
(8+5 z+4 z^2)\text{}+(7 z+6 z^47 z^5)w+(3 z^2z^3)w^2+(8 z2 z^42...

Oct1512 08:18 AM
jackmell

0 
875 
I'm not sure if this is the right forum.
I'm actually trying to solve this for a computer program
given shape A...

Oct1312 10:10 PM
Muphrid

1 
1,449 