This page (copyrighted by John Polking)
is a wonderful resource for studying differential equations. There are two programs: One for graphing the direction field of first-order differential equations in the form: x' = f(t,x); One for graphing the phase portrait for system of differential equations of the for dx/dt = f(x,y), dy/dt = g(x,y). Below are some screenshots of what the program looks like:
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| Control window for phase plane graphing. |
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| The result window. |
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| Another result. |
I find these programs very helpful not to mention IMMENSELY fun to play around with. As a bonus, they had the Matlab versions on their page too!
