Probablity question (confused on the pdf)

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SUMMARY

The discussion centers on the probability density function (pdf) defined as \( f(x) = 7(4)^{-i} \) for \( x \in (\frac{1}{2^{i}},\frac{1}{2^{i-1}}] \) where \( i = 1, 2, 3, \ldots \). A participant expresses confusion regarding the value of \( P(x) \) when \( x = \frac{3}{4} \), questioning why it exceeds 1. The resolution clarifies that while the pdf integrates to 1, it does not need to be bounded by 1 for all values of \( x \) within its domain, as demonstrated by the example of a uniform distribution over the interval [0, 1/2].

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Homework Statement

<br /> $f(x)=\begin{cases}<br /> 7(4)^{-i} &amp; x\in(\frac{1}{2^{i}},\frac{1}{2^{i-1}}],i=1,2,3,...\\<br /> 0 &amp; 0\geq x,x&gt;1<br /> \end{cases}$ (please excuse the poor latex)<br /> <h2>Homework Equations</h2><br /> <br /> <br /> <br /> <h2>The Attempt at a Solution</h2><br /> the problem I&#039;m having is say x=3/4. then according to the pdf, shouldn&#039;t P(x)=7*(4^-1)=7/4&gt;1. i mean, shouldn&#039;t it be bounded by 1? when i integrate this out, i get 1, like i should, so I&#039;m not sure what mistake I&#039;m making.
 
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what is the actual question? Maybe I'm missing it, but it seems like you just posted an equation without any description of what you are trying to do
 
Why do you expect that a pdf must be bounded by 1? Consider a random variable that is uniformly distributed over the interval [0, 1/2]. Is that pdf bounded by 1?
 
well, the actual problem is show that this function is a pdf. so i need to show that it integrates to 1, which it does, but i believe i also need to show that it's bounded by 0 and 1 for all x in the domain, which is the problem I'm having a hard time with.
 
oh, got it. duh. thank you.
 

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