Open main menu
Home
Random
Recent changes
Special pages
Community portal
Preferences
About Wikipedia
Disclaimers
Incubator escapee wiki
Search
User menu
Talk
Dark mode
Contributions
Create account
Log in
Editing
Rolle's theorem
(section)
Warning:
You are not logged in. Your IP address will be publicly visible if you make any edits. If you
log in
or
create an account
, your edits will be attributed to your username, along with other benefits.
Anti-spam check. Do
not
fill this in!
===Proof=== The proof uses [[mathematical induction]]. The case {{math|1=''n'' = 1}} is simply the standard version of Rolle's theorem. For {{math|''n'' > 1}}, take as the induction hypothesis that the generalization is true for {{math|''n'' β 1}}. We want to prove it for {{mvar|n}}. Assume the function {{mvar|f}} satisfies the hypotheses of the theorem. By the standard version of Rolle's theorem, for every integer {{mvar|k}} from 1 to {{mvar|n}}, there exists a {{mvar|c<sub>k</sub>}} in the open interval {{open-open|''a<sub>k</sub>'', ''b<sub>k</sub>''}} such that {{math|1=''f ''β²(''c<sub>k</sub>'') = 0}}. Hence, the first derivative satisfies the assumptions on the {{math|''n'' β 1}} closed intervals {{math|[''c''<sub>1</sub>, ''c''<sub>2</sub>], β¦, [''c''<sub>''n'' β 1</sub>, ''c<sub>n</sub>'']}}. By the induction hypothesis, there is a {{mvar|c}} such that the {{math|(''n'' β 1)}}st derivative of {{math|''f ''β²}} at {{mvar|c}} is zero.
Edit summary
(Briefly describe your changes)
By publishing changes, you agree to the
Terms of Use
, and you irrevocably agree to release your contribution under the
CC BY-SA 4.0 License
and the
GFDL
. You agree that a hyperlink or URL is sufficient attribution under the Creative Commons license.
Cancel
Editing help
(opens in new window)