Critical point of a piecewise function

In summary, the conversation discusses the concept of a critical point in a function, which is defined as a point where the function is either not differentiable or the derivative is equal to zero. The definition from Wikipedia is mentioned and it is concluded that the answer to the question is yes, the point in question can be considered a critical point. However, different definitions may lead to different answers. The discussion also touches on the use of critical points in finding minima and maxima in a function.
  • #1
mohammed El-Kady
32
2
TL;DR Summary
critical point to piece wise function
If the function is not differentiable at point. Can we consider this point is critical point to the function?
f(x) = (x-3)^2 when x>0
= (x+3)^2 when x<0
he asked for critical points in the closed interval -2, 2
 
Physics news on Phys.org
  • #2
Please define critical point.
 
  • #3
Math_QED said:
Please define critical point.
you don't know it?
 
  • #4
" When dealing with functions of a real variable, a critical point is a point in the domain of the function where the function is either not differentiable or the derivative is equal to zero." definition from Wikipedia Looks like the answer is yes. (derivative discontinuous)
 
  • #5
mohammed El-Kady said:
you don't know it?

Different people use different definitions... The answer to your question depends on the definition you are using.
 
  • Like
Likes berkeman
  • #6
mathman said:
" When dealing with functions of a real variable, a critical point is a point in the domain of the function where the function is either not differentiable or the derivative is equal to zero." definition from Wikipedia Looks like the answer is yes. (derivative discontinuous)
thank you
 
  • #7
Math_QED said:
Different people use different definitions... The answer to your question depends on the definition you are using.
I don't know which definition the problem ask for. I know the definition of the derivative, but someone solved it with the differentiability , so i need to be sure from it.
 
  • #8
critical point vis-a-vis finding minima/maxima? Yes, you have to evaluate those points. Think of a "V" shaped function. How else would you find the minimum.
 
  • #9
I don't think you meant to do this, but you have not defined the function at x=0, so it is not a critical point of the function.
 

FAQ: Critical point of a piecewise function

1. What is the critical point of a piecewise function?

The critical point of a piecewise function is a point where the function is not continuous, meaning there is a break or discontinuity in the graph. This can occur when the function changes from one defined equation to another, resulting in a sharp or abrupt change in the graph.

2. How do you find the critical point of a piecewise function?

To find the critical point of a piecewise function, you need to first identify the points where the function changes from one equation to another. Then, you can evaluate the function at those points to determine if there is a discontinuity. If there is, that point is considered a critical point.

3. Why is the critical point important in a piecewise function?

The critical point is important in a piecewise function because it can affect the behavior and interpretation of the function. It can also impact the domain and range of the function, as well as the continuity and differentiability of the function at that point.

4. Can a piecewise function have multiple critical points?

Yes, a piecewise function can have multiple critical points. This can occur when there are multiple breaks or discontinuities in the graph, resulting in multiple points where the function is not continuous.

5. How can the critical point of a piecewise function be used in real-world applications?

The critical point of a piecewise function can be used in real-world applications to analyze and model phenomena that involve sudden changes or discontinuities. This can include situations like phase changes in materials, abrupt changes in population growth, or changes in stock prices.

Similar threads

Replies
5
Views
2K
Replies
1
Views
2K
Replies
4
Views
1K
Replies
3
Views
3K
Replies
1
Views
1K
Replies
1
Views
1K
Back
Top