Find Limit: (2-x)/(x+2)(x-2)

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In summary, a limit in mathematics represents the value that a function approaches as the input value gets closer and closer to a specific value. To find the limit of a function, you can substitute the approaching value into the function or use algebraic manipulation/graphing. The limit of the given function (2-x)/(x+2)(x-2) is undefined because the function is undefined at x = 2 and x = -2. The limit of a function can be proven using the epsilon-delta definition. Finding the limit of a function is important as it helps us understand the behavior of a function and determine key properties, and can be used to solve more complex problems.
  • #1
screamtrumpet
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lim (2-x)/(x^2-4)
x>2

Find the limit(is it exists)

The substitution method failed so I factored the bottomto (x+2)(x-2).Where do I go from here?
 
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  • #2
A very important but often overlooked "law of limits":

If f(x)= g(x) for all x except x= a, then [itex]\displaytype\lim_{x\to a}f(x)= \lim_{x\to a} g(x)[/itex].

Here, for all x except x= 2, (2- x)/(x-2)(x+2)= -1/(x+2).
 
  • #3
use l'Hospital's rule
 
  • #4
Thank you
 

1. What is a limit?

A limit in mathematics represents the value that a function approaches as the input value gets closer and closer to a specific value.

2. How do you find the limit of a function?

To find the limit of a function, you need to substitute the value that the function is approaching into the function and evaluate the result. You may also use algebraic manipulation or graphing to determine the limit.

3. What is the limit of the given function, (2-x)/(x+2)(x-2)?

The limit of the given function is undefined. This is because the function is undefined at x = 2 and x = -2, and as x approaches these values, the function becomes undefined.

4. How can you prove the limit of a function?

The limit of a function can be proven using the epsilon-delta definition, where you can show that for any small value of epsilon, there exists a corresponding value of delta that will make the distance between the limit and the function value less than epsilon.

5. What is the significance of finding the limit of a function?

Finding the limit of a function is important in calculus and other areas of mathematics as it helps us understand the behavior of a function near a specific input value. It also allows us to determine key properties of a function, such as continuity and differentiability, and can be used to solve more complex problems in mathematics and science.

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