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I wish to solve the following set of ODE. $ $ i\frac{d}{dt}B_{n}\left(t\right) =f\sqrt{\left(P-n\right)\left(n+1\right)}B_{n+1}\left(t\right)+f\sqrt{n\left(P-n+1\right)}B_{n-1}\left(t\right) + Y\left[\left(P-n\right)\left(P-n-1\right)+n\left(n-1\right)\right]B_{n}\left(t\right)$ $ The question is similar to the Solving n simultaneous differential equation.It’s working perfectly for N=2 case. But the method is not giving any results for larger N with larger time say t=0 to 3000, and varying constants. Values ofRead more

y=C/(x+1) ( I get it from sol=DSolve[y'[x]==-y[x]/(x+1),y[x],x]) How I can plot this “sol” with showing tangets in list of points ?Read more

Please someone help me get away with this, write a mathematica programme for this equation containing both partial differential equations and Laplace transform. u_m (x,t)=k_m u_(m-1) (x,t)+hL^(-1) {R_m (u ⃗_(m-1) )} Where: R_m (u ⃗_(m-1) )=L[u_(m-1) ]-(1-2/n)(x^2/s)+1/s^α L[-x (∂u_(m-1))/∂x-x^2/12 (∂^2 u_(m-1))/(∂x^2 )] L→Laplce transformation and L^(-1)→inverse laplace transformation,Read more

I am trying to solve a system of 54 second order equations using NSolve. I create a list with the 54 variables and they appear in this way: {Subscript[a, \[Alpha]][1, 1], Subscript[a, \[Alpha]][2, 0], Subscript[a, \[Alpha]][2, 2], Subscript[a, \[Alpha]][3, 1], Subscript[a, \[Alpha]][3, 3], …} I also define the 54 equations in another table in theRead more

Is there a Mathematica command that is a combination of Contour3D and ParametricPlot3D? It would be something like this: ParaContour3D[f==0, g==0, h==0, {t,0,1}, {x,-3,3}, {y,-3,3}, {z,-3,3}] f, g, h are implicit equations for x, y, and z in terms of t. For example, we may have f = t^2 x^2 + t x + 2xRead more

I am trying to solve following PDE’s for functions Xt,Xx,Xy using DSolve but to no avail- killing={2(Xt^(1,0,0))[t,x,y]==0 ,(Xt^(0,1,0))[t,x,y]+(Xx^(1,0,0))[t,x,y]==0 ,(Xt^(0,0,1))[t,x,y]+(Xy^(1,0,0))[t,x,y]==0 ,2(Xx^(0,1,0))[t,x,y]==0 ,(Xx^(0,0,1))[t,x,y]+(Xy^(0,1,0))[t,x,y]==0 ,2(Xy^(0,0,1))[t,x,y]==0}; DSolve[killing, {Xt[t, x, y], Xx[t, x, y], Xy[t, x, y]}, {t, x, y}]; Can anyone help me figure out the problem.Read more

I am trying to write up a paper with some results form Mathematica (11.2) among other things. I need to know what algorithm does it use when I solve a system of polynomial equations which is underdetermined (infinitely many solutions). In particular, sometimes Mathematica also find real solutions that are embedded into the complex positive-dimensionalRead more

i’m very new in Mathematica. I want to solve the Bethe Ansatz Equations for the so-called “Hofstadter-Problem”. These are equations in the Form like: $ $ z^2_{l}=q^{Q}*\prod^{Q-1}_{m\neq l}\frac{q^2*z_{l}-z_{m}}{z_{l}-q^2*z_{m}}$ $ for $ $ l=1,…,Q-1$ $ , $ q$ is just a complex number $ $ q=e^{i \pi \frac{P}{Q}}$ $ , and Q is an integer. SoRead more

If I have an extremely long list of simultaneous Partial Differential Equations (too long to manually write) that looks like OutputCases=\begin{align}\left\{v(1)^{(0,1)}(x,t)+r x-e^{\rho t}+t y,r x v(1)^{(1,0)}(x,t)-2 e^{\rho t} v(1)^{(1,0)}\(x,t)+\rho t e^{-\rho t} v(1)^{(1,0)}(x,t)+t y v(1)^{(1,0)}(x,t)+v(2)^{(0,1)}(x,t),\\text{OutputSizeLimit$ \grave{ }$ Skeleton}(22),\\rho t e^{-\rho t} v(2)^{(1,0)}(x,t) \left(v(5)^{(1,0)}(x,t)\right)^4+4 \rho t e^{-\rho t} v(3)^{(1,0)}(x,t) v(4)^{(1,0)}(x,t) \left(v(5)^{(1,0)}(x,t)\right)^3\+2 \rho t e^{-\rho t} \left(v(4)^{(1,0)}(x,t)\right)^3Read more

I have the following set of 14 differential equations with the variables listed. When I run it, a message comes “Repeated convergence test failure..” \[Alpha] = 1.5; \[CapitalDelta]1 = 2 \[Pi]*1.45*10^6; \[CapitalDelta]2 = 2 \[Pi]*1.45*10^6; k1 = 2 \[Pi]*759*10^3; k2 = 2 \[Pi]*759*10^3; g1[k1_, k2_, \[Alpha]_] = \[Alpha]/4 (k1 + k2); A1[k1_, \[CapitalDelta]1_] = (I*k1)/2Read more