What is the Limit of a Function in Two Variables at the Origin?

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Homework Statement



lim (x,y)\rightarrow(0,0) f(x,y)=2*x/(x^{2} + x +y^{2})

Homework Equations



used different paths like y=k*x ,where k is a constant and y=k*x^2

The Attempt at a Solution


Got an answer 2 but solution says does not exist. Can anybody convince me that why limit does not exist,without using polar form.

I am currently studying in 1st year of college.
 
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The problem with the paths you chose is that there is one direction you are unable to represent with a finite k. What direction do you think that would be?
 
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oh got it thanks man. its the y axis! The limit comes out to be zero if i put x=1. Thanks!
 
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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