@Kitonum thank you very much, your solution work! I just wonder what's wrong with the use x->f(x) in this case?

@raziabdul 

Thanks for the reply. I am still waiting for my first two questions: 

1. Do I only need creating Maple worksheets, establishing interfaces and uploading the worksheets at an appropriate server in order to be able using MapleNet without any additional software? 

2. Can MapleNet display both GUI-based and command-driven-based Maplets on the web? Loeky