- #1
Combinatorics
- 36
- 5
Homework Statement
Find a differential of second order of a function [itex]u=f(x,y)[/itex] with continuous partial derivatives up to third order at least.Hint: Take a look at [itex]du[/itex] as a function of the variables [itex]x[/itex], [itex]y[/itex], [itex]dx[/itex], [itex]dy[/itex]:
[itex]du= F(x,y,dx,dy)=u_xdx +u_ydy[/itex].
Homework Equations
The Attempt at a Solution
I'll be glad to receive some guidance regarding the following:
1) Does the second order differential is assumed to be:
[itex] d^2 f = ( \frac{ \partial}{ \partial x_1} \Delta x_1 +\frac{ \partial}{ \partial x_2} \Delta x_2 ) ^n f [/itex] ?
2) If so, how should I solve this question? Thanks in advance !