MHB Evaluating limit of 2 variable function

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The limit of the function as (x, y) approaches (0, 0) is evaluated along the x-axis and y-axis. Along the x-axis, the limit evaluates to 1, while along the y-axis, it evaluates to -1. Since the two limits are different, it confirms that the limit does not exist. This conclusion is correct based on the evaluations provided. The discussion highlights the importance of checking limits from multiple paths in multivariable calculus.
tmt1
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I have

$$\lim_{{(x, y)}\to{(0, 0)}} \frac{x^4 - y^4}{x^4 + x^2y^2 + y^4}$$

If I evaluate the limit along the x-axis, I get

$$\lim_{{(x, y)}\to{(0, 0)}} \frac{x^4 - y^4}{x^4 + x^2y^2 + y^4}$$

which evaluates to $1$.

If I evaluate the limit along the y-axis, I get

$$\lim_{{y}\to{0}} \frac{ - y^4}{ y^4}$$

which evaluates to $-1$.

Since the 2 limits are different, then the limit does not exist. Is this correct?
 
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