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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
do you understand how you differentiate like x^2 without the limit formula?( x^2 becomes 2x.)
you need to know that before you can do partial differentiation.
When it is partial differentiation you differently 3 different times for you equation.
one for x, one for y and one for z.
for the x equation you differentiate 2(x^2 +z)y + x/(z^2) treat X as the variable and treat y&z as constants.
Fx=(4·x·y·z^2 + 1)/z^2
Fy=2·(x^2 + z)
Fz=2·(y·z^3 - x)/z^3
i am fully aware how to partially differentiate functions however i am being asked to do it from 1st principles and this is what is causing me problems.
It works the same way as normal differentiation from first principles as the other variables are treated as constants.