I have a very very basic question on CDF and limits

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In summary, the conversation was about a question related to calculus that the professor was not going to go over in an "introduction to probability" class. The question asked about determining the right continuity and left limits of given functions at specific values. The conversation also included the speaker's confusion about the question and a request for guidance.
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Roni1985
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I am taking an "introduction to probability" class and there is a question (related to calculus) that the professor is not going to go over it.

Here is the question:
1. For a random variable X, the function F defined by
F(x) = P(X <= x),−inf < x < inf
is called the cumulative distribution function of X. A property of every distribution function F is that
it is right continuous with left limits.
For the following functions, determine if they are right continuous and/or have left limits at the
indicated values. (A “yes” or “no” answer is insufficient. Justify your answers or no credit will be
given.)
(a) at x = 0 and x = 1 for G(x) = |x|/x .
(b) at x = 0 and x = 1 for H(x) = arctan(x).

Well, if we look at 'a', I was trying to find the limit when x->0+ and limit when x->0-. I am getting -1 and 1
but the function is not defined at x=0.
and it's not right continuous nor left continuous, and it has right and left limits, correct?

OR I don't get the question.

Can somebody tell me what I need to do here or lead me to the correct way ??

Thanks in advance,
Roni.
 
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ops, didn't see you have a homework forum :/
 

Related to I have a very very basic question on CDF and limits

1. What is a CDF?

A CDF (cumulative distribution function) is a mathematical function that shows the probability of a random variable being less than or equal to a specific value. It is often used to describe the distribution of a continuous random variable.

2. How is a CDF different from a PDF?

A CDF gives the cumulative probability of a random variable, while a PDF (probability density function) gives the probability of a random variable taking on a specific value. The CDF takes into account all values up to a given point, while the PDF only looks at a specific point.

3. What does it mean for a CDF to approach a limit?

When a CDF approaches a limit, it means that the probability of a random variable being less than or equal to a certain value is approaching a specific value. This can be useful in determining the behavior of a random variable as it approaches a certain point.

4. How can CDFs be used in statistical analysis?

CDFs can be used to determine the probability of a random variable falling within a certain range of values. They can also be used to compare different distributions and make predictions about the likelihood of certain outcomes.

5. What are some key properties of a CDF?

Some key properties of a CDF include: it is a non-decreasing function, it approaches 0 at negative infinity and 1 at positive infinity, and it is continuous (except at possible points of discontinuity).

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