What's difference between these?(derivation)

[Hamid1]

Hi all.
I know concept of derivation but I don't know the differences between these:
http://hamid693.persiangig.com/qu.jpg
can anyone explain what's difference between these?(1 to 5)

Thanks(and excuse me for my probable English mistakes

 

[tiny-tim]

Hi Hamid1!

(1) I've no idea what that is

(2) H is a function one variable only, G, and dH/dG is the rate of change

(3) H is a function of variables including x, and H_x is the rate of change of H if x is changed, but the other variables are constant; H_x is also written ∂H/∂x

(4) H is a function of variables including x and y, and H_xy = (H_x)_y = (H_y)_x = ∂²H/∂x∂y

(5) G is a function of one variable only, and G' is the rate of change