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Multiple Choice
Given the graph of , find a number such that if , then .
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Verified step by step guidance
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Understand the problem: This is a problem about the formal definition of a limit. Specifically, we are trying to find a value of δ (delta) such that if the distance between x and 3 is less than δ, then the distance between f(x) and 2 is less than 0.5. This is related to the ε-δ definition of a limit.
Recall the ε-δ definition of a limit: For a function f(x), the limit as x approaches a value c is L if, for every ε > 0, there exists a δ > 0 such that 0 < |x - c| < δ implies |f(x) - L| < ε. Here, ε = 0.5, c = 3, and L = 2.
Analyze the graph of f(x): Look at the graph of f(x) near x = 3. Determine how close x needs to be to 3 (i.e., the value of δ) to ensure that |f(x) - 2| < 0.5. This involves observing the behavior of f(x) around x = 3.
Test the given δ values: For each δ value provided (δ = 2, δ = 0.5, δ = 1.5, δ = 0.2), check whether the condition 0 < |x - 3| < δ implies |f(x) - 2| < 0.5. This can be done by examining the graph or using the function's behavior.
Select the correct δ: The correct δ is the largest value that satisfies the condition. If δ = 0.5 works, but δ = 1.5 does not, then δ = 0.5 is the correct choice. Verify this by ensuring that for δ = 0.5, the inequality |f(x) - 2| < 0.5 holds for all x such that 0 < |x - 3| < δ.