How do you move floors and ceilings in discrete math?

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    Discrete Discrete math
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Discussion Overview

The discussion revolves around the manipulation of floor and ceiling functions in the context of discrete mathematics, particularly focusing on how to handle logarithmic expressions and inequalities involving these functions. Participants explore various methods for simplifying or canceling these functions in mathematical expressions.

Discussion Character

  • Technical explanation
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant suggests that to eliminate a logarithm from an expression, raising the base to the power of the inequality is a valid approach, although this is contested by others.
  • Another participant argues against the method of raising the expression by base 10, indicating that it is incorrect.
  • There is a discussion about how to handle ceiling functions in inequalities, with one participant asking for clarification on the entire problem to provide a more accurate response.
  • A later reply proposes that assuming certain conditions (like z > 0) leads to a similar case for ceiling functions, questioning what the largest value of the expression can be under those conditions.

Areas of Agreement / Disagreement

Participants express differing views on the correct methods for manipulating logarithmic and ceiling functions, indicating that there is no consensus on the approaches discussed.

Contextual Notes

Some participants' claims depend on specific assumptions about the variables involved, such as the positivity of z, which may not be universally applicable. The discussion also highlights unresolved mathematical steps related to the manipulation of logarithmic and ceiling functions.

iScience
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The title more accurately should have been "How do you cancel floors and ceilings in discrete functions"

For instance,

##\frac{log{\frac{3x}{-6(z)}}}{8t} < 1##

If I wanted to get rid of the log, I'd just raise the expression by base 10.

##\frac{(\frac{3x}{-6(z)})}{10^{8t}} < 10^1##

But what happens if there's a roof for discrete functions?

##\frac{\lceil{log \frac{10x}{4y}}\rceil}{8z} < 1##

How do I handle this?

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EDIT NOTICE: the expressions above have been fixed into its their proper inequalities
 
Last edited:
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iScience said:
For instance,

##\frac{log{\frac{3x}{-6(z)}}}{8t}##

If I wanted to get rid of the log, I'd just raise the expression by base 10.

##\frac{(\frac{3x}{-6(z)})}{10^{8t}}##
i rather hope you would not do that, since it is wrong.
 
oops, sorry, here's the other side

##\frac{log(stuff)}{8t} < 1 ##

##\frac{stuff}{10^{8t}} < 10 ##
 
iScience said:
oops, sorry, here's the other side

##\frac{log(stuff)}{8t} < 1 ##

##\frac{stuff}{10^{8t}} < 10 ##
Still wrong.

##\frac{\log(stuff)}{8t} < 1 ##
##\log(stuff)<8t##
##stuff<10^{8t}##
For your ceil question, it might help if you state the entire problem.
 
iScience said:
But what happens if there's a roof for discrete functions?

##\frac{\lceil{log \frac{10x}{4y}}\rceil}{8z} < 1##
Assuming z>0, z>0 leads to a very similar case:
##\lceil{stuff\rceil} < 8z##
What is the largest value of stuff that satisfies the inequality? Once you found that, you can continue with the usual approaches.
 

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