For which function f(x, y) does lim_((x,y)→(0,0)) f(x, y) exist ?

PYQ UPPSC LT Grade (Assistant Teacher) 2025

1. A.

   f(x,y)=(x²−y²)/(x²+y²)

2. B.

   f(x,y)=xy/√(x²+y²)

3. C.

   f(x,y)=x²y²/[x²y²+(x−y)⁴]

4. D.

   f(x,y)=xy/(x²+y²)

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