Very basic noob question about integers

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    Integers Noob
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Discussion Overview

The discussion revolves around the understanding of integers, specifically the properties of negative and positive numbers in the context of absolute values and functions. Participants explore the implications of the absolute value function and its behavior with negative inputs.

Discussion Character

  • Conceptual clarification, Exploratory

Main Points Raised

  • One participant expresses confusion about the statement that |-x| = max{-x, x}, questioning how -x can be greater than x.
  • Another participant provides an example with x = -5, illustrating that -x can be larger than x when x is negative.
  • A third participant notes that -x is not necessarily negative, depending on the value of x, and emphasizes the importance of considering the sign of x.
  • One participant acknowledges the simplicity of the question after receiving explanations, indicating a sense of relief.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the initial confusion, but they provide various perspectives that clarify the relationship between negative and positive numbers in different contexts.

Contextual Notes

The discussion highlights the dependency on the value of x and the conditions under which -x is evaluated, which may lead to different interpretations of the absolute value function.

fission
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hi all so this is a very basic question i think and i feel very bad for tumbling here but still i need to clear this, so from childhood i was taught that the negative numbers are less than positive but now when i am studying limits and functions i came across absolute function and it said |-x| = max{-x,x}. alright seems legit but now the book says that max of the two is -x and that's why function came out positive due to double minus sign, so i want to ask how is -x greater than x or i am doing something wrong here? thanks for ur help
 
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If x=-5, then -x=-(-5)=5 is larger than x=-5.

If x is negative, -x is larger than x, otherwise it is not.
 
It's just something that tricks your brain until you think about it for a second.

Q: Is ## -x ## is a negative number?
A: Not necessarily.

You don't know what ##x## is. If ## x = -3 ## then ## -x =-(-3) = 3 ## which is positive.

I prefer to have the absolute value function written piecewise:

Absolute-Value-as-Piecewise-Function2.png
 
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duh! lol that was really a simple one xD but thanks everyone for giving a good explanation :)
 

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