4c190e…: “Apart from the humid disk”

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Consider $F(x,y) = \frac {xy^2-y^4}{x^2-y^4}$ . Compute the limit $\lim _{\vector {x,y}\to \vector {4,2}} F(x,y) = \answer {1/2}$ (write DNE if the limit does not exist)

Is $F(x,y)$ continuous at $(4,2)$ ?

Yes No

Note that although the limit exists, the function is not defined at $(4,2)$ .