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MathewsMD

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- Thread starter MathewsMD
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- #1

MathewsMD

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- #2

Office_Shredder

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[tex] \lim_{x\to 0} f(x) g(x) [/tex]

but you cannot split it into two limits and give the new expression any meaning.

- #3

Mark44

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This wiki article has a table of indeterminate forms - http://en.wikipedia.org/wiki/Indeterminate_form#List_of_indeterminate_forms

- #4

SteamKing

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The limit of f(x) = 1/x as x approaches 0 is not zero, it is infinity.

- #5

Mark44

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You're sort of half correct.The limit of f(x) = 1/x as x approaches 0 is not zero, it is infinity.

$$\lim_{x \to 0^+}\frac 1 x = ∞$$

$$\lim_{x \to 0^-}\frac 1 x = -∞$$

Since the one-sided limits aren't equal, the two-sided limit doesn't exist.

- #6

MathewsMD

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Sorry for my poor phrasing.

How about in this new example.

y = [limx→0^+ 1/x][limz→0 (1 - cosz)/z]

Would it be possible to evaluate this limit since one limit approaches infinity while the other approaches 0, and they are different variables in this case.

How about in this new example.

y = [limx→0^+ 1/x][limz→0 (1 - cosz)/z]

Would it be possible to evaluate this limit since one limit approaches infinity while the other approaches 0, and they are different variables in this case.

Last edited:

- #7

Mark44

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No, you're right back to what I was talking about in post #3, and what you had in your first post. The fact that you have different variables does not change things.Sorry for my poor phrasing.

How about in this new example.

y = [limx→0^+ 1/x][limz→0 (1 - cosz)/z]

Would it be possible to evaluate this limit since one limit approaches infinity while the other approaches 0, and they are different variables in this case.

- #8

Mark44

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How did this limit come up? What's the problem you're trying to solve?

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