Continuity of g(x,y) = (xy)^1/3

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Homework Statement



Show if the function g(x,y) = (xy)1/3 is continuous at the point (0,0)

Homework Equations





The Attempt at a Solution



I'm a bit confused. When I take the limit as (x,y)->(0,0) I get that L = 0, and the function is equal to 0 at (0,0), but when I plot the function in maple, it seems as if there is a discontinuity along the line x =0 and y = 0. I am ultimately trying to show if the function is differentiable at (0,0). Any help?
 
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Well, your calculations are correct. The function is continuous.

Many function graphers cannot handle the cube root well, which is likely the reason that it doesn't show up nice in maple.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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