Use the formal definition of limits

Pjy3fD0X8yUIn summary, the conversation is about using the formal definition of limits to prove a statement. The person asking for help is struggling with writing a coherent argument and is directed to watch a video for further assistance.
  • #1
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Homework Statement


Use The Formal definition of limits to show
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Homework Equations


The Formal definition of limits


The Attempt at a Solution



Tried to do it like this, but that was wrong. What do i need to do different?
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  • #2
What you wrote has little resemblance to a proof. A proof is an argument showing that some statement is true. First, you should identify what statement it is you're trying to prove. Second, and this is key, you need to write a coherent argument where it's logically clear how you started from the givens and reached the conclusion.

You may find this video helpful:

 
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FAQ: Use the formal definition of limits

What is the formal definition of limits?

The formal definition of limits is a mathematical concept that describes the behavior of a function as its input approaches a certain value, usually denoted by x. It states that the limit of a function f(x) as x approaches a value a is a number L, if for any positive number ε, there exists a positive number δ such that if the distance between x and a is less than δ, then the distance between f(x) and L is less than ε.

Why is it important to use the formal definition of limits?

The formal definition of limits is important because it provides a precise and rigorous way to understand the behavior of a function as its input approaches a certain value. It allows us to make accurate predictions and calculations in mathematics and science.

How do you determine if a limit exists using the formal definition?

To determine if a limit exists using the formal definition, you need to find a value L that the function approaches as x gets closer and closer to a. This can be done by finding the limit of the function at both sides of the value a and making sure they are equal. If they are equal, then the limit exists. If they are not equal, then the limit does not exist.

Can the formal definition of limits be used for all functions?

Yes, the formal definition of limits can be used for all functions, including continuous and discontinuous functions. However, certain functions may require different techniques and methods to determine their limits.

What are some real-world applications of using the formal definition of limits?

The formal definition of limits has many real-world applications, such as in physics, engineering, and economics. It can be used to calculate the maximum and minimum values of a function, predict the behavior of a system, and analyze the stability of a structure. It is also used in optimization problems to find the most efficient solution.

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