Is the given function differentiable at the endpoints on the interval [0,5]?

  • Context: MHB 
  • Thread starter Thread starter karush
  • Start date Start date
  • Tags Tags
    Mean Value
Click For Summary
SUMMARY

The function \( f(x) = \sqrt{x(5-x)} \) is continuous on the interval \([0, 5]\) but not differentiable at the endpoints due to vertical slopes. The Mean Value Theorem (MVT) applies here, stating that if a function is continuous on a closed interval and differentiable on the open interval, there exists at least one point \( c \) in the interval where the derivative equals the average rate of change. In this case, the function meets the continuity requirement but fails differentiability at the endpoints, which is crucial for MVT applicability.

PREREQUISITES
  • Understanding of the Mean Value Theorem (MVT)
  • Basic knowledge of calculus, specifically derivatives
  • Familiarity with continuity and differentiability concepts
  • Graphing functions and interpreting their behavior
NEXT STEPS
  • Study the implications of the Mean Value Theorem in calculus
  • Learn about differentiability conditions at endpoints
  • Explore the graphical representation of functions and their derivatives
  • Investigate examples of functions that are continuous but not differentiable
USEFUL FOR

Students and educators in calculus, mathematicians analyzing function behavior, and anyone seeking to understand the application of the Mean Value Theorem in real-world scenarios.

karush
Gold Member
MHB
Messages
3,240
Reaction score
5
Does the function satisfy the hypothesis of the mean value theorem
On the given interval, give reasons for your answer

$$f\left(x\right)=\sqrt{x\left(5-x\right)},\ \ \left[0,5\right]$$

The graph of this is the top half of a circle

My answer was
It is continuous at all points on the interval but not differential at the endpoints due to vertical slopes.

This answer was not correct.?

MVT $$f'\left(c\right)=\frac{f\left(b\right)-f\left(a\right)}{b-a}$$
 
Physics news on Phys.org
karush said:
Does the function satisfy the hypothesis of the mean value theorem
On the given interval, give reasons for your answer

$$f\left(x\right)=\sqrt{x\left(5-x\right)},\ \ \left[0,5\right]$$

The graph of this is the top half of a circle

My answer was
It is continuous at all points on the interval but not differential at the endpoints due to vertical slopes.

This answer was not correct.?

MVT $$f'\left(c\right)=\frac{f\left(b\right)-f\left(a\right)}{b-a}$$

What is your hypothesis about the MVT?
 
Not sure, the book didn't address where $f'$ is undefined
 
karush said:
Not sure, the book didn't address where $f'$ is undefined

I don't think you understand the mean value theorem very well. It states that if your function is continuous everywhere and smooth at all points except the endpoints, then the gradient of any chord on that function is the same as the gradient of the function at some point in between. So your derivative doesn't need to be defined at the endpoints...
 
OK, thanks.
 

Similar threads

  • · Replies 11 ·
Replies
11
Views
2K
Replies
3
Views
2K
  • · Replies 46 ·
2
Replies
46
Views
5K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 12 ·
Replies
12
Views
3K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 9 ·
Replies
9
Views
1K