Odd Functions and Their Derivatives: A Theorem

  • Thread starter Zaare
  • Start date
  • Tags
    Function
In summary, an odd function is a mathematical function that satisfies the property f(-x) = -f(x) and has a graph that is symmetric about the origin. To determine if a function is odd, one can substitute -x for x and simplify or look at the graph for symmetry. The derivative of an odd function is an even function and has the same symmetry as the original function. An odd function can have a derivative at all points as long as it is differentiable, but may not have a derivative at sharp points or corners.
  • #1
Zaare
54
0
It seems the derivate of an odd function [tex](f(-x)=-f(x))[/tex] is an even function [tex](f(-x)=f(x))[/tex], and vice versa. Is there a theroem about this?
 
Physics news on Phys.org
  • #2
Suppose f is odd. We have that (f(-x))' = (-f(x))' = -f'(x). But by the chain rule, (f(-x))' = -f'(-x). Thus -f'(-x) = -f'(x) <=> f'(-x) = f'(x) <=> f' is even.
 
  • #3
Ah, that was easy. Thank you. :)
 

FAQ: Odd Functions and Their Derivatives: A Theorem

What is the definition of an odd function?

An odd function is a mathematical function that satisfies the property f(-x) = -f(x), meaning that when the input is negative, the output is the negative of the output when the input is positive. This results in the graph of an odd function being symmetric about the origin.

How can you determine if a function is odd?

To determine if a function is odd, you can substitute -x for x in the function and simplify. If the resulting function is equal to the negative of the original function, then the function is odd. Another way is to look at the graph of the function and see if it is symmetric about the origin.

What is the derivative of an odd function?

The derivative of an odd function is an even function. This is because the derivative of -x is -1, which is a constant and therefore an even function. This means that the slope of an odd function is symmetric about the y-axis.

How does the derivative of an odd function relate to its symmetry?

The derivative of an odd function being an even function means that the slope of an odd function is symmetric about the y-axis. This also means that the derivative of an odd function has the same symmetry as the original function, meaning that the graph of the derivative is also symmetric about the origin.

Can an odd function have a derivative at all points?

Yes, an odd function can have a derivative at all points, as long as the function is differentiable at those points. This means that the function is continuous and has a well-defined slope at each point. However, if the function has a sharp point or corner, the derivative may not exist at that point.

Similar threads

Replies
2
Views
1K
Replies
12
Views
1K
Replies
14
Views
2K
Replies
9
Views
1K
Replies
3
Views
3K
Replies
5
Views
2K
Back
Top