Which Is Greater: f(-2) or f(10)?

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Discussion Overview

The discussion revolves around comparing the values of the function f at two points, f(-2) and f(10), based on the provided derivative f'(x) = (1/4)x(x-6). Participants explore the implications of the derivative's graph and its symmetry, while also considering the limitations of not being able to directly integrate to find f(x).

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant requests assistance in determining whether f(-2) or f(10) is greater, given the derivative f'(x).
  • Another participant notes that the graph of f'(x) is a parabola symmetric about x=3, and discusses the distances from -2 and 10 to this point of symmetry.
  • A different participant challenges the symmetry argument by providing specific values for f(-2) and f(8), suggesting that f(x) is not symmetric about x=3.
  • One participant expresses uncertainty about proving that f(10) is greater than f(-2) without using integration, acknowledging the limitations of their current tools.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the comparison of f(-2) and f(10). While some suggest that f(10) is greater, others question the validity of this conclusion and the reasoning behind it.

Contextual Notes

Participants reference specific values for f(-2) and f(8) derived from an integral function, which may imply limitations in the assumptions made about the behavior of f(x) based on f'(x). The discussion also highlights the challenge of proving claims without direct integration.

Sonata4004
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Would you please help me with the question:

The graph of derivative f'(x)= (1/4)x(x-6) is given.
What value is greater f(-2) or f(10)?
It is permitted to sketch f(x) using f'(x) graph, but you can not take the integral of f'(x) directly.
 
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Is that supposed to be f'(x)= (1/4)x(x-6)? The graph of that is a parabola which is symmetric about x= 3. The distance from -2 to 3 is 5 while the distance from 3 to 10 is 7.
 
Thank you for reply,
The graph f(x) is not exactly symmetrical about x=3 since f(-2)=-3.67 while f(8)=-5.33, though the distance from 3 to -2 and 8 is the same.
The data is taken from integral function y=(1/12)x^3-(3/4)x^2.
 
Does anybody have other suggestions? Or maybe some elaboration on the symmetry idea? It is right that f(10)>f(-2), but I don't know solid proof for this unless taking integral, which is out of range of permitted tools
 

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