Proving Limit Exists: x-2 of f(x)=2

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In summary, the conversation discusses how to prove that a delta exists such that when [x] < delta, then f(x) > 1 using the delta, epsilon definition of a limit. One participant suggests using the equation [x-a] < delta such that f(x) > 1, but they are unsure how to prove it. The conversation ends with the question of whether f(x) = 2 is a constant function or if the limit is being proven. The thread is then closed and the participants are asked to repost their question.
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rb120134
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Homework Statement
Prove that delta>0 exists such that f(x)>1 using delta epsilon definition
Relevant Equations
[x-a]<delta such that f(x)>1
Given is the following: lim x-2 of f(x)=2 prove (using delta, epsilon definition of a limit) that a delta exists so that when [x]<delta then f(x)>1
I came up with when [x-a]<delta (f(a)-epsilon<f(x)< f(a) + epsilon) so f(a)-epsilon>1 so epsilon<f(a) -1 but I don't know how to prove this or how to answer this question?
 
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Perhaps someone else can make sense of that, but that is just a muddle to me. What is the question exactly?
 
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rb120134 said:
Homework Statement:: Prove that delta>0 exists such that f(x)>1 using delta epsilon definition
Relevant Equations:: [x-a]<delta such that f(x)>1

Given is the following: lim x-2 of f(x)=2 prove (using delta, epsilon definition of a limit) that a delta exists so that when [x]<delta then f(x)>1
I came up with when [x-a]<delta (f(a)-epsilon<f(x)< f(a) + epsilon) so f(a)-epsilon>1 so epsilon<f(a) -1 but I don't know how to prove this or how to answer this question?
I agree with PeroK's assessment.
Is it given that f(x) = 2 is a constant function, or are you trying to prove this limit?
$$\lim_{x \to 2} f(x) = 2$$

Thread closed. Please repost your question.
 
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