Prove that the derivative of an odd function is even

Since f(-x) = -f(x), the derivative of f(-x) with respect to x is -f'(x), which is the negative of the derivative of f(x) with respect to x. This means that the derivative of an odd function is even. Similarly, the derivative of f(x) with respect to x is f'(x), which is the same as the derivative of -f(-x) with respect to -x. Therefore, the derivative of an even function is odd. In summary, the derivative of an odd function is even and the derivative of an even function is odd, which can be proven using the limit definition or the chain rule.
  • #1
NWeid1
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A function f is an even function is f(-x)=f(x) for all x and is an odd function is f(-x)=-f(x) for all x. Prove that the derivative of an odd function is even and the derivative of an even function is off. I get what even and odd functions are but I'm not sure how to rigorously prove this. Thanks.
 
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  • #2
NWeid1 said:
A function f is an even function is f(-x)=f(x) for all x and is an odd function is f(-x)=-f(x) for all x. Prove that the derivative of an odd function is even and the derivative of an even function is off. I get what even and odd functions are but I'm not sure how to rigorously prove this. Thanks.

One way to do this is to use the limit definition of the derivative.

PS - don't delete the parts of the posting template.
 
  • #3
Or, and I think simpler, use the chain rule to differentiate f(-x) with respect to x.
 

FAQ: Prove that the derivative of an odd function is even

What is an odd function?

An odd function is a mathematical function that satisfies the property f(-x) = -f(x) for all values of x. This means that the function is symmetric about the origin, with equal values on either side. Examples of odd functions include sine, tangent, and cube root functions.

What is a derivative?

A derivative is a measure of how a function changes as its input changes. It is calculated by taking the limit of the ratio of the change in the output of a function to the change in its input, as the change in the input approaches zero.

How do you prove that the derivative of an odd function is even?

To prove that the derivative of an odd function is even, we use the definition of an odd function and the properties of derivatives. We substitute -x for x in the function, and use the chain rule to show that the derivative of the new function is equal to the negative of the original function. This proves that the derivative of an odd function is even.

Why is it important to know the derivative of an odd function?

Knowing the derivative of an odd function is important because it allows us to simplify calculations and solve problems involving odd functions. It also helps us understand the properties and behavior of odd functions, which can be useful in various fields of science and engineering.

Are there any exceptions to the rule that the derivative of an odd function is even?

No, the rule that the derivative of an odd function is even holds true for all odd functions. However, it is important to note that not all functions are odd or even, and this rule only applies to odd functions. Functions that are neither odd nor even do not follow this rule.

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