Does the limit of (x²y)/(x⁴+y²) as (x,y)→(0,0) exist?

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What is:
lim(x,y)->(0,0) of (x^2)(y) / ((x^4) + (y^2)) ?

When I take x_n = 0, y_n = 1/n, lim=0
and x_n = 1/n, y_n = 0, lim=0
and x_n = y_n = 1/n, lim=0
All three limits are zero, yet other people I've asked say the limit doesn't
exist. Am I right, or am I doing something wrong here? Thanks.
 
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[tex]\lim_{(x,y) \rightarrow (0,0)}\frac{x^2y}{x^4+y^2}[/tex][tex]x=0[/tex]
[tex]\lim_{(x,y) \rightarrow (0,0)}\frac{0\cdot y}{0+y^2}=0[/tex][tex]y=0[/tex]
[tex]\lim_{(x,y) \rightarrow (0,0)}\frac{x^2\cdot 0}{x^4+0}=0[/tex][tex]y=x^2[/tex]
[tex]\lim_{(x,x^2) \rightarrow (0,0)}\frac{x^4}{2x^4}=\frac 1 2[/tex]

Aim to make your powers the same, use [tex]y=x^2[/tex] or [tex]x=y^2[/tex].

General tests:

[tex]x=y=0[/tex]
[tex]y=x[/tex]
[tex]x=y^n[/tex]
[tex]y=x^n[/tex]
 
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