Plotting a Continuous Function Graph with Given Data

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Discussion Overview

The discussion revolves around the challenge of plotting a continuous function graph based on a set of specified properties related to the function and its derivatives. Participants explore the implications of these properties and whether they can coexist without contradiction.

Discussion Character

  • Debate/contested

Main Points Raised

  • One participant presents a set of conditions for a continuous function, including specific values at certain points and behavior of the first derivative.
  • Another participant attempts to verify the conditions and points out that some requirements are not satisfied based on the provided properties.
  • A later reply highlights an inherent contradiction in the requirements, specifically referencing Rolle's Theorem and the implications of the derivative conditions.
  • Further clarification is requested regarding the original problem statement and the language used in the posts.
  • One participant expresses difficulty in understanding the requirements without a graph.
  • Another participant reiterates that the conditions cannot all be satisfied, confirming the contradiction identified earlier.
  • A final response indicates acceptance of the impossibility of creating a graph that meets all the stated properties.

Areas of Agreement / Disagreement

Participants generally agree that the conditions presented contain contradictions, making it impossible to satisfy all of them simultaneously. However, there is no consensus on how to resolve the issue or clarify the original problem statement.

Contextual Notes

The discussion reveals limitations in the clarity of the original problem statement and the language used, which may affect understanding and communication among participants.

leprofece
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Plot a continue function graph with the following data o properties f(0)= 0 f of (-1) = 0 f of first derivative in 0 = 0?
f of first derivative in (1) = 0
first derivative (x) > 0 in x >1 and (0,1)
first derivative (x) < 0 in x < -1 and -1<x<0
see my graph is it correct?? where am I wrong

View attachment 2727
 

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leprofece said:
Plot a continue function graph with the following data o properties f(0)= 0 f of (-1) = 0 f of first derivative in 0 = 0?
f of first derivative in (1) = 0
first derivative (x) > 0 in x >1 and (0,1)
first derivative (x) < 0 in x < -1 and -1<x<0
see my graph is it correct?? where am I wrong

View attachment 2727

It's a bit difficult to decipher your requirements. Let me see if I have them correct here:

\begin{align*}
f(0)&=0 \quad \text{satisfied} \\
f(-1)&=0 \quad \text{not satisfied} \\
f'(0)&=0 \quad \text{satisfied} \\
f'(1)&=0 \quad \text{not satisfied} \\
f'(x)&>0 \; \forall \, x>1 \; \text{or} \; 0<x<1 \quad \text{satisfied} \\
f'(x)&<0 \; \forall \, x<-1 \; \text{or} \; -1<x<0 \quad \text{not satisfied}
\end{align*}
 
we keep on bad
Why is not satisfied?? in this two points?' without a graph is for me very difficult to understand
 
If what I wrote is indeed your requirements, there is an inherent contradiction. You require a continuous function on $[-1,0]$, and the requirement $f'(x)<0$ whenever $-1<x<0$ implies that $f$ is differentiable on $(-1,0)$. But then Rolle's Theorem implies there must be a $c\in(-1,0)$ such that $f'(c)=0$, contradicting your last requirement that $f'(x)<0$ for all $-1<x<0$.

The requirements that I wrote down cannot all be satisfied. Could you please state the original problem, word-for-word?

Also, could you please write understandable English, as per http://mathhelpboards.com/rules/? I am not able to decipher your posts.
 
Sketch a continuous graph with the following properties:

f(0)=0
f(-1)=0
f′(0)=0
f′(1)=0
f′(x)>0 for 0<x<1 and x>1
f′(x)<0 for (-1,0) and x<-1

About my english it is sorry to say I am from a latin Country and my mother tongue is not english
Ackbach said:
If what I wrote is indeed your requirements, there is an inherent contradiction. You require a continuous function on $[-1,0]$, and the requirement $f'(x)<0$ whenever $-1<x<0$ implies that $f$ is differentiable on $(-1,0)$. But then Rolle's Theorem implies there must be a $c\in(-1,0)$ such that $f'(c)=0$, contradicting your last requirement that $f'(x)<0$ for all $-1<x<0$.

The requirements that I wrote down cannot all be satisfied. Could you please state the original problem, word-for-word?

Also, could you please write understandable English, as per http://mathhelpboards.com/rules/? I am not able to decipher your posts.
 
leprofece said:
Sketch a continuous graph with the following properties:

f(0)=0
f(-1)=0
f′(0)=0
f′(1)=0
f′(x)>0 for 0<x<1 and x>1
f′(x)<0 for (-1,0) and x<-1

About my english it is sorry to say I am from a latin Country and my mother tongue is not english

Thank you. Yes, the first two conditions contradict the last condition. It's not possible to create a graph with all these properties.
 
no way thanks
 

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