# Tagged Questions

90 views

### Solving an ODE with Mathematica, using Lagrangian mechanics

Question: The velocity of light above a hot surface decreases with the height from that surface. The velocity is given by $v=v_0(\frac{1-y}{\alpha})$ where $y$ is the vertical distance above the ...
241 views

### How to make Runge-Kutta for solving nonlinear ODE system in Mathematica

How to make Runge Kutta method for system of non linear equations in this Matrix form. Matrices A3, B3 and B4 are functions of matrix X3. Initial conditions are X1=X2=X3=X4=0 and system is here  ...
164 views

### Precision and time of calculating the integral in Mathematica

1)How to calculate this integral, because I have some very small values (10^-20) in solution and values on this position in matrix should be equal to zero. If I can not do that with working precision, ...
622 views

### NDSolve simple matrix problem in mathematica

I have a problem with command NDSolve in mathematica. If we have simple second order differential equation, it is easy to write code in mathematica. But if we have matrix problem (for example 4 ...
How to make simple iteration in Mathematica for this three equations and save $q$ for each step. If we define $q'=dq/dx$, $q''=dq'/dx$ we have two equations (1) ...