- #1
Thomas_
- 21
- 0
Homework Statement
Let :
[tex]f(x,y) = \frac{xy(x^2 - y^2)}{(x^2 + y^2)^2}[/tex] if [tex](x,y) \neq (0,0)[/tex]
[tex]f(x,y) = 0[/tex] if [tex](x,y) = (0,0)[/tex]
a) Find [tex]f_{xx}(0,0)[/tex]
b) Find [tex]f_{xy}(0,0)[/tex]
c) Find [tex]f_{yx}(0,0)[/tex]
Homework Equations
None
The Attempt at a Solution
I'm not sure how to deal with the piecewise defined function, I just took the first and second partial derivatives w/ respect to x (for part a), but then still I can't evaluate the resulting function at (0,0), because at the point it doesn't exist...