How Can You Compute Multivariable Limits in Mathematica?

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springo
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Homework Statement


I would like to be able to compute multivariable limits with a CAS. I have Mathematica, Derive and an HP 50g.
For example, how would I compute:
[tex]\lim_{(x,y)\rightarrow(0,0)}\frac{x^2}{y}[/tex]

Homework Equations



The Attempt at a Solution


On Mathematica I tried:
Code:
Limit[x^2/y, {x, y} -> {0, 0}]
(doesn't work)
Code:
Limit[x^2/y /. {y -> f[x]}, x -> 0]
(I think this could work, but I need to figure out what f[x] has to be)

Thanks for your help.
 
The limit in your example does not exist (it is undefined), because it depends on how you approach (0,0). For example, f(t,t)->0 as t->0 from the right, but f(sqrt(t),t)->1 as t->0 from the right.
 
yyat said:
The limit in your example does not exist (it is undefined), because it depends on how you approach (0,0). For example, f(t,t)->0 as t->0 from the right, but f(sqrt(t),t)->1 as t->0 from the right.
OK, sorry for choosing a wrong example, I'm just starting multivariable calculus. Anyway for existing limits, is there any way to compute them using a CAS?