Question

In: Statistics and Probability

[25 pts] The probability density function of a random variable X is fX(x) = ce^ -|x|...

[25 pts] The probability density function of a random variable X is fX(x) = ce^ -|x| for all values of x, where c is a constant. Find the value of c and the cumulative distribution function of X.

Solutions

Expert Solution

We are given a random variable X with probability density function given by:

[The support of X is the set of real numbers since the question mentions that for 'all values of x']

Now, we know that the integral of the probability density function of X integrated over the entire support of X must integrate to 1, thus we get:

Now, we find the cumulative distribution function of x.

When x<0, the cumulative distribution function of X is given by:

When x ≥ 0, the cumulative distribution function of X is given by:

Combining equations (1) and (2), we get the cumulative distribution function of X:

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