Help with Cas program

[johna]

Hi Michael and Helge, apologies for not replying earlier to your advice.

In the end, I used the integral template enclosed in single quotes and used a variable other than X for the upper limit.
A simple L1(var):=Eval(F1); worked!!
No use of Cas. or Cas("L1():=..."). Really confusing at times.

By the way Michael, if I used lower case x in defining the function in Home view,as suggested, results in an error.
Thanks to both of you for the suggestions.
Regards
John