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Dustinsfl
Oct30-09, 10:02 PM
lim (x^2-4y^2)/(x+2y) as (x,y)->(-2,1)
Does this limit go to -4 or DNE since it is undefined all along x+2y?

HallsofIvy
Oct31-09, 04:04 AM
It Does Not Exist.

arildno
Nov1-09, 07:28 AM
Please note that you may write this as:
\frac{x^{2}-4y^{2}}{x+2y}=\frac{(x-2y)(x+2y)}{x+2y}=x-2y,x\neq{-}2y