Which is Greater? $\cos(\cos 1))$ vs $\cos(\cos(\cos 1)))$

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Discussion Overview

The discussion centers around comparing the values of the expressions $\cos(\cos 1)$ and $\cos(\cos(\cos 1))$. Participants explore this comparison through various approaches, including graphical representation and dynamical systems perspectives.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification

Main Points Raised

  • One participant illustrates the comparison using a dynamical systems perspective, referencing a graph where the brown curve represents $y=\cos x$ and the blue line represents $y=x$.
  • Another participant expresses gratitude for the solution provided by kaliprasad and mentions solving the problem in a similar manner.
  • A third participant thanks Opalg for providing a graph that aids in the understanding of the problem.

Areas of Agreement / Disagreement

The discussion does not indicate a consensus on which expression is greater, as it primarily focuses on illustrating methods and sharing insights rather than reaching a definitive conclusion.

Contextual Notes

Participants reference graphical methods and dynamical systems without detailing specific assumptions or mathematical steps involved in their reasoning.

Who May Find This Useful

Individuals interested in mathematical comparisons, dynamical systems, or graphical analysis may find this discussion relevant.

anemone
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Determine which of the following is greater?

$\cos(\cos 1))$ or $\cos(\cos(\cos 1)))$
 
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anemone said:
Determine which of the following is greater?

$\cos(\cos 1))$ or $\cos(\cos(\cos 1)))$

we have $\cos 1 < 1$
so $\cos(\cos 1) > (\cos 1)$
so $\cos(\cos(\cos 1)) < \cos (\cos 1))$
Hence $2^{nd}$ term is larger

above is using the fact that $\cos{t} < 1 < \frac{\pi}{2}$ and for $a > b$ $\cos (a) < \cos (b) $
 
Last edited:
Just to illustrate kaliprasad's solution (from a dynamical systems perspective):
[sp]The brown curve is $y=\cos x$, the blue line is $y=x$.
View attachment 5480
[/sp]
 

Attachments

  • cos.png
    cos.png
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Thanks kaliprasad for your solution! I solved it the same way you did!

A special thanks to Opalg for attaching the graph for illustration purpose! I appreciate it!
 

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