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

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SUMMARY

The discussion centers on proving the limit of a function f(x) as x approaches 2 equals 2, specifically demonstrating that a delta exists such that when |x - 2| < delta, then f(x) > 1. The delta-epsilon definition of limits is employed, with the user attempting to establish that epsilon must be less than f(a) - 1. However, clarity on whether f(x) is a constant function or if the limit is being proven remains ambiguous, leading to confusion in the proof process.

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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.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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