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

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SUMMARY

The limit of the function f(x,y) = 2x/(x² + x + y²) as (x,y) approaches (0,0) does not exist. Various paths were tested, including y = kx and y = kx², leading to different results. Specifically, when approaching along the y-axis (where x=0), the limit evaluates to zero, while other paths yield a limit of 2. This discrepancy confirms that the limit is path-dependent and therefore does not exist.

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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!
 

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