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finding the derivative of u.
I try to find the derivative of u.
somehow i not clear with the meaning of this equation.
can someone explain to me? thanks in advanced.
kindly refer to attached mathcad15 file.
It looks to me that you use xi both as varaible name AND as function name. This will not work.
When you want to define a function you also have to state which variable(s) it should depend on.
f(x):=,,,,term in x ...
Are you looking for something like this:
