perplexus.info :: Calculus : Double differential equation

Double differential equation (Posted on 2008-06-26)

Find all injective functions f, defined for all x>0, satisfying f(f'(x))=-f(x)

No Solution Yet Submitted by Jonathan Lindgren

Rating: 2.5000 (2 votes)

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Puzzle Thoughts

Comment 3 of 3 |

f(x) = ln(x) is the required function.

Edited on February 15, 2023, 11:32 am

Posted by K Sengupta on 2023-02-15 11:31:28

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