Recent content by bayan

thanks for your reply. Did NDSolve with the options given work for you? or do you recommend the use of another software to solve those odes? btw is that code for mathematica? Regards

Hi, I need to solve 3 coupled first order ODE's using NDSolve (numerical solution). This is the code I have used ; NDSolve[{u'[t] == ((1 - (u[t]/t^2))/(-3 - (u[t]/t^2) - (v[t]/t^2))), v'[t] == (((u[t]/t^2) - (v[t]/t^2))/(-3 - (u[t]/t^2) - (v[t]/t^2))), w'[t] == (v[t])/(-3 t^2 - (u[t]) -...

For part a) it says to find the flux piercing a cube, if cube encloses all 4 charges then you don't need integration. I am also doing a similar assignment and for part c) I think they want us to find the forces that the other 3 charges apply to one. i.e force that charge 2,3,4 exert on 1 and...

Homework Statement what is the probability of finding an electron with energy between 5eV and 5.5eV at T=300k, given that the fermi energy of the metal is 4.2 eV. Homework Equations ##P(E,T)dE= \frac{3}{2} E_F^\frac {-3}{2} \frac{E^\frac{1}{2}}{e^\frac{E-E_F}{K_B T}+1}dE## The...

Thanks for your help

Given that (0,0) is defined would I be correct in saying the function in undefined only at (-1,0) hence ##D= R## except ##x=-1, y=0## ? Regards

Thanks, so the limit is at (-1,0) is 0 regardless of the path taken ( which would be represented by θ) right? also did I have the right idea in regards to the domain of the funtion? all ##ℝ## ##|y≠0## , ##x≠-1,0|## Regards

a little bit, but this one is confusing me for some reason (possibly lack of experience with limits) ## \frac {0}{0} ## would be undermined, right? so this is how I have gone with factoring it: ## \frac{(r cos θ -1)r cos θ (r sin θ)^2}{r^2} = \frac {(r^2 cos^2 θ - r cos θ)r^2 sin ^2...

Thanks, so in polar coordinates the function can be written as \displaystyle \ \frac{(rcosθ-1)rcosθ(rsinθ)^2}{r^2} and just subbing \displaystyle r=0 yields to \displaystyle \frac {0}{0} or do I need to further simplify the function in polar form and then sub in \displaystyle r=0 Also...

Thanks for your replies, I am a bit rusty with polar coordinates but using y=mx I get the following with the function. [SIZE="3"] \frac {(x-1)xm^2x^2}{x^2+m^2x^2} \frac {(x-1)xm^2x^2}{x^2(m^2+1)} \frac {(x-1)xm^2}{m^2+1} \frac {m^2x^2-m^2x}{m^2+1} is this the right method...

Thanks for your replies, I missed a - sign in my OP, so the denominator goes to zero if[SIZE="1"] x=-1 y=0 or [SIZE="1"]y^2=-(x+1)^2 and numerator goes to zero if [SIZE="1"]x=0 or [SIZE="1"]x=-1 By shifting curve to the right I get the following for the function \frac{(x-1)xy^2}{x^2+y^2}...

Homework Statement Find the limit (if it exists) and domain of the following function. (I do not need to use epsilon delta proof, just results on different curves to prove this) \stackrel{lim}{_{(x,y)→(−1,0)}} [SIZE="4"] \frac {x(x+1)y^2}{(x+1)^2+y^2} Homework Equations The Attempt at a...

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Hi and thank you for your reply. I ended up with the following ρ-ρ1/ρ2-ρ1 = l2/l Does that seem ok?

Hi, sorry I had - minus sign in my hand written workout, for some reason I must have put a plus sign, another one where I only put l1=l-l2 at the end lead me to l2/l=(ρ-ρ1(l-l2))/(ρ2) Still end up with l & l2 on both sides for some reason I will upload hand written workout in a few hours