Boundary value problem: local stifness matrix

sara_87
Messages
748
Reaction score
0

Homework Statement



Given a BVP:

\Delta(u)+u=1 in \Omega
u=0 on \partial\Omega
using linear piecewise functions,
calculate the corresponding local stiffness matrix on the reference triangle :
{(x,y); 0<=x<=1, 0<=y<=1-x}.

The domain is a square with one point in the middle (at (0.5,0.5))

Homework Equations





The Attempt at a Solution



Does anyone know where i can start?
 
Physics news on Phys.org
which numerical method are you using?
 
I am using the finite element method.
I forgot to mention, i fixed my problem, i know how to do this question :)
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
Back
Top