Extended Mean Value Theorem

Theorem

Let $f$ be a real function which is continuous on the closed interval $\closedint a b$ and differentiable on the open interval $\openint a b$.

Let $f'$ be the derivative of $f$.

Let $f'$ also be a real function which is continuous on the closed interval $\closedint a b$ and differentiable on the open interval $\openint a b$.


Then:

$\exists \xi \in \openint a b: \map f b = \map f a + \paren {b - a} \map {f'} a + \dfrac 1 {2!} \paren {b - a}^2 \map {f' '} \xi$


Proof


This theorem requires a proof.
You can help $\mathsf{Pr} \infty \mathsf{fWiki}$ by crafting such a proof.
To discuss this page in more detail, feel free to use the talk page.
When this work has been completed, you may remove this instance of {{ProofWanted}} from the code.
If you would welcome a second opinion as to whether your work is correct, add a call to {{Proofread}} the page.


Also known as

The is also known as the second mean value theorem.

Some sources hyphenate: extended mean-value theorem or second mean-value theorem.


Also see


Sources

  • 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): mean-value theorem
  • 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): mean-value theorem