hi guys wondering if u could help.

iv got a question that involves partial differentiation but it involves doing it from first prinicples

i kno the way to do normal differentiation from first principles....

dy/dx = limit as h tends to zero [f(x+h) - f(x)]/h etc etc

however i dont know what to do when its partial differentiation

the function is f(x,y,z) = 2(x^2 +z)y + x/(z^2)

hope u can help me!

rcd