Find the median of the probability distribution

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Homework Help Overview

The problem involves finding the median of a probability distribution defined by the function f(x) = C|x-2| for the interval 0 <= x <= 3, with f(x) = 0 otherwise. Participants are exploring how to set up the integral to find the median and are discussing the implications of the absolute value in the function.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss solving for the constant C and setting up the integral to find the median, questioning how to handle the absolute value in the function. There is confusion about the limits of integration and the value of m, with suggestions to graph the function for better understanding.

Discussion Status

The discussion is ongoing, with participants sharing their attempts and questioning the setup of the integral. Some guidance has been offered regarding the integration limits and the behavior of the absolute value function, but no consensus has been reached on the correct approach.

Contextual Notes

Participants are navigating the challenge of integrating a piecewise function due to the absolute value, and there is uncertainty regarding the placement of m in relation to the value of 2.

Phox
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Homework Statement



f(x) = C|x-2| for 0 <= x <= 3
f(x) = 0 otherwise

Homework Equations





The Attempt at a Solution


Solved for C, found it to be (2/5).

So.. I'm confused how to set up my integral here. I tried integral(2/3(x-2)dx) from m to 3 = 1/2. That didn't yield the correct result.
 
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Phox said:

Homework Statement



f(x) = C|x-2| for 0 <= x <= 3
f(x) = 0 otherwise

Homework Equations



The Attempt at a Solution


Solved for C, found it to be (2/5).

So.. I'm confused how to set up my integral here. I tried integral(2/3(x-2)dx) from m to 3 = 1/2. That didn't yield the correct result.
If you found C to be 2/5, then the integral should be
[itex]\displaystyle \int_{M}^{3}\frac{2}{5}|x-2|\,dx \ .[/itex]​

Set that equal to 1/2 and solve for M, although it might be easier to integrate from 0 to M.

Graph the integrand to see why.
 
Last edited:
SammyS said:
If you found C to be 2/5, then the integral should be
[itex]\displaystyle \int_{M}^{3}\frac{2}{5}|x-2|\,dx \ .[/itex]​

Set that equal to 1/2 and solve for M, although it might be easier to integrate from 0 to m.

Graph the integrand to see why.

Yes, actually that's what I meant to say. I don't understand how I can integrate the function having the absolute value there. I understand how to do it if it were say.. integrating from 0 to 3. But since we don't know what m is I don't understand.

And neither does wolfram alpha lol
 
Phox said:
Yes, actually that's what I meant to say. I don't understand how I can integrate the function having the absolute value there. I understand how to do it if it were say.. integrating from 0 to 3. But since we don't know what m is I don't understand.

And neither does wolfram alpha lol
Did you graph the function?

If x ≤ 2, then |x - 2| = 2 - x .

If x ≥ 2, then |x - 2| = x - 2 .
 
Last edited:
Yes, and I understand that. What I don't understand is where m lies. Is it in the range of <2 or >2
 
Phox said:
Yes, and I understand that. What I don't understand is where m lies. Is it in the range of <2 or >2

That is what you need to figure out. If in doubt, try it both ways to see what happens! However, careful examination of your graph should be enough.
 

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