cheers dan, your method is easy to understand. it's frustrating trying to learn all this calculus on your own when there is just a huge pile of books and you're forever researching. so i appreciate your help.

just a question though, on the 2nd epsilon identity you used:

what i wanted to ask is: do you have to use the imn notation.. or can you use any preferred notation.. such as ixy....

i understand the final result will still be the same as long as the notation is consistent throughout the solution, but i just wanted to confirm whether imn has to be used as a standard for vector calculus. thanks once again .:o