15 Reputation

2 years, 219 days

Perfect!...

@Rouben Rostamian

Perfect. Many many thanks. This has brought me a lot further. I would still have a little question ...

How can I get the expression:

`sin(k1*(c*t-x))`

change to these:

`-sin(k1*(x-c*t)) `
Thanks again!

fg

New problem description...

Thank you for the quick response and sorry for the unclear description.

I try to describe my problem again.

The approach function

`u := a(x)*sin(k1*(-c*t+x))`

is used in the following pde:

`pde := diff(u(x, t), t, t)-c^2*(diff(u(x, t), x, x));`

That is, I have simply formed the appropriate derivatives. The goal later is to determine the variable a(x). I would like to control this "hand calculation". With "pdsolve" I have the problem to integrate the approach function "u" correctly with. "pdetest" is a good suggestion as a last step for comparison. But how do I get here?

Many many thanks again!

Way to solution...

Many thanks for the help!
We now come to the following solution:

`-c^2*(d^2*a*sin(k1*(-c*t+x))/dx^2+2*d*a*k1*cos(k1*(-c*t+x))/dx)`

which intermediate steps would I have to insert this in maple yet? Since I have to check several approach functions, I want to "automate" the control as much as possible.

Thanks a lot!

Frank

Started successfully...

Hello,

Thank you for the help and tips. I'll get on quite well with that.