Probability distribution and finding the median

Painguy
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Homework Statement


Suppose that x measures the time (in hours) it takes for students to complete an exam. All students are done within 2 hours and the density function for x is given by

f(x)={(x^3)/4 0<x<2
{0 otherwise

Compute the median of this distribution. (Give an exact answer.)


Homework Equations



int f(x)dx from m to inf =1/2

The Attempt at a Solution



I'm not sure what m is supposed to be, and because of that I'm completely lost. It looks like the integral doesn't even converge. How do I go about this problem?
 
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Painguy said:

Homework Statement


Suppose that x measures the time (in hours) it takes for students to complete an exam. All students are done within 2 hours and the density function for x is given by

f(x)={(x^3)/4 0<x<2
{0 otherwise

Compute the median of this distribution. (Give an exact answer.)

Homework Equations



int f(x)dx from m to inf =1/2

The Attempt at a Solution



I'm not sure what m is supposed to be, and because of that I'm completely lost. It looks like the integral doesn't even converge. How do I go about this problem?

Yes, it does converge. f(x)=0 for x>2 and x<0. You aren't really integrating to infinity. Now get started.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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