Return Styles: Pseud0ch, Terminal, Valhalla, NES, Geocities, Blue Moon. Entire thread

Monsieur Ejemplé

Name: !Ep8pui8Vw2 2007-08-27 18:14 ID:tRXLIMo6

Give an example of a function f:R^2 --> R where both partial derivatives df/dx and df/dy exist non-trivially, but neither are continuous at (0,0).

Name: Anonymous 2007-08-29 18:09 ID:u8Y/NBHX

I'd assume some function of the form

f(x,y) = xsin1/x + ysin1/y

should suffice.

I'm extrapolating from my knowledge of functions of a single parameter, but xsin1/x and ysin1/y are both continous functions, so I'd assume the addition would be continous.

However df/dx|y isn't continous and neither is df/dy|x.

Am I right?

Newer Posts
Don't change these.
Name: Email:
Entire Thread Thread List