How to integrate with trapezoidal method the following equation?

Hey community,

I want to integrate a equation like: { ((dX/d_teta) / (A-X) }*d_teta where A is dependend on teta!!

My source of which this equation is out of reccomends the trapezoidal method.

Before I need to integrate the upper equation, it says i should integrate dX/d_teta with Runge-Kutta 4. order. So there should be a value for dX/d_teta. This value should be X right? That means the upper equation is simplified to value_for_X * integral [1/(A - value_for_X) *d_teta], right?

How can I integrate this with trapezoidal methode?

Thank you for your help!!!

[darova]

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