Limit in Two Variables: Approaching the 0/0 Case

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tysonk
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How do I approach such question,
0/0 case in two variables, I can't find a simplification.

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Thanks for the help.
 
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Look for two ways to approach (0,0) that will give you different limits. That will prove the limit doesn't exist and you don't have to worry about it anymore.
 
isn't it -1?

edit: oh got it

2nd edit: nope still got -1

I approached from both possible y's
 
veneficus5 said:
isn't it -1?

edit: oh got it

2nd edit: nope still got -1

I approached from both possible y's

Look at the limit as y->0 when x=0 and the limit as x->0 when y=0.
 
I learned that one can plug in things like y=x, y=2x to help determine whether a limit can exist. If a different value is obtained then a limit may not exist.
Is it still possible to plug in y=x^3

Because when we plug in y=x and y=x^3 we get different values. Thanks.
 
tysonk said:
I learned that one can plug in things like y=x, y=2x to help determine whether a limit can exist. If a different value is obtained then a limit may not exist.
Is it still possible to plug in y=x^3

Because when we plug in y=x and y=x^3 we get different values. Thanks.

Sure. That works. I still think x=0 and y=0 are easier, but it's your choice.