given the following functions:
z^2 = x^2 + y^2
What would be the proper way of differentiating it? My instincts tell me it should be 2z = 2x + 2y, but I've been told it's not always correct because of what respect you're deriving the function from or to.
Can anyone show me an easy way to remember all these derivative rules rather than just pure memorization? It's ok if it's only a few things I just have no choice but to memorize, but it seems as though my professor and this book want me to just "memorize" things rather than learn it and prove it if I ever needed to.
Thanks in advance to any/all replies.
P.S. Are there any other zones/sites where I can ask these kinds of questions and get back faster responses? The quality of responses in this zone so far are impeccable, but it's a bit frustrating when I have to wait an entire day for a solution to a problem and times isn't on my side. Not annoyed, just curious. Thanks again.