I'm trying to transform a partial differential equation (PDE) into an ordinary differential equation (ODE) as demonstrated in the paper. However, I find some steps confusing and difficult to follow. The process often feels chaotic, and managing the complexity of the equations is overwhelming. Could you suggest an effective and systematic method to handle such transformations more easily?

Download transform-pde-to-ode-hard_example.mw

Is there a way to determine how we can construct a system of equations from this complex PDE? Also, moderator, you mentioned I could create a new question using the branch option, but you deleted my previous question, which led me to delete my earlier post. don't delete this one.

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this equation will be solve by changing variable but when  i found the function and substitute the ODE is not zero where  is mistake?

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I try to get some Bilinear form for some PDE equation  and already i have algorithm by writing in lecture but i can't apply i don't what is mistake i did, and i didn't seen some of this lecture code in maple  like (myint(expr,var))
 i  do upload PIcture of algorithm and example which they get Bilinear form 

Bilinear.mw

thanks for any help

why i take intgral from equation it must apply for each term but just by sign is show up how it will work?

Download int.mw