Hi Im trying to do Q1 and Q2(a) on this past exam sheet and am having alot of trouble . I attached the Pdf cos im not sure how to use LAtex.

Any help is very much appreciated

Q1b Do i need to calculate the partial derivatives using the definition. im confused s the function is defined in 2 parts. If you can calculate the directional derivatives at (0,0) how can you also show that it is NOT differentiable at (0,0)

Q2(a) I get b =Log(m)/Log(e) might be wrong but then i cant see how to use that for the next part.

THANKS!