@JorgeFernández-Hidalgo Your question is definitely perfectly sensible. What you're asking, as I read it, is are there differentiable functions that we can show are differentiable but not with the differentiation rules?

Thus, folks who point to the fact that the rules are easy are completely missing the point. To answer the question, you've got to find differentiable functions where the rules are not applicable. There are many such and I posted a response with a couple.

I saw the answer, thanks for the message ! @MarkMcClure

Please consider reopening this question. The crux of the question, as I read it, is: are there functions that are differentiable but not by the basic algebraic rules of differentiation. The commentary and at least one answer seems to indicate confusion over this so my affirmative answer is, perhaps, pleasantly surprising.

I should point out that I edited out an erroneous example that invalidates the accepted answer. That was not my intention but it seemed the only way to edit it for clarity to potentially reopen it. It's also worth mentioning that @quid indicates that the question is not bad.

[ SmokeDetector | MS ] Few unique characters in answer, no whitespace in answer (183): "Why do I always get 1 when I keep hitting the square root button on my calculator?" by Oscar Cutts-White on math.SE

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delete 1, 2, 3, 4

@JoséCarlosSantos I voted to delete the first and the last. but 2, 3 will soon be Roomda's (there are not answers, the questions have been closed.)

→ 1 message moved to ­Trash

The author of this answer wants to have it deleted (some some reason he cannot delete it himself) – one more delete vote is needed.

@MartinR It's gone. This user has run into a problem others have, where posting an answer to a question from one's phone, can not be deleted from one's phone.

@amWhy It's possible to delete on the phone by opening it in the browser. The app has an option to do that. But the Android app indeed has no option to delete.

I don't know if I am in the right room, but my weak convergence question isn't getting any feedback. if consists in proving weak convergence of a sequence of functions in L^p

@MarkMcClure I restored it partly with an "Initially"; I'll wait a bit how it evolves and might reopen myself later.

@MattSamuel Thanks for the clarification!

@quid That is reasonable - thanks.

delete please

🤮 math.stackexchange.com/q/3932052/29335

@rschwieb Very fitting emoticon!

@Measureme You really do not ask any question, nor do you state in your "question" statement that you want others' feedback. Typically answer fields are reserved to answers the answer is confident is true. If you wanted feedback on a proposed solution to the question you did not articulate, then provide the proposed solution in the question post, as well as what your proposed answer is answering, and choose the additional tag "solution verification" (and allow others to respond in answering.)

As your question and answer currently stand, you asked a question and answered it. Why would others offer feedback when you never asked for it? As a rule, users typically don't offer feedback on answers, more so on questions, when such feedback is explicitly asked for by the OP

Well, i didn't ask explicitly a question, but I expressed what my need was: "I wanted to know if you have ideas on proving it in a simple manner". Anyways you are right, i should make my request more obvious and especially appealing.

@Measureme No problem! It is good to ask for feedback, like you did here. Wish you the best! :-)

Hi, @PaulSinclair!

Should I just delete the question and re-ask it better so it gets seen?

@Measureme That's generally discouraged. Editing the question will also make it more visible, though to a lesser extent admittedly.

That's fine, i'll wait. Thank you!

@MattSamuel If you like word games, please join us in the newest such word game here.

@Measureme You too, @Measureme, @MartinSleziak, @MartinR !! ^^^^^^

@amWhy I'd love to, but unfortunately I'm working. Thank you for the invitation.

@MattSamuel Any time! :-)

@amWhy Thanks, but I was just looking in because I didn't recognize the acronym!

@PaulSinclair No problem! Your welcome here there, anywhere in math.se chats, and likely elsewhere, too!

Please consider closing

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