# Thread: Problem of cumulative distribution

1. ## Problem of cumulative distribution

i cant find the constant when i integrate the density function ...

2. IS 0<x<1? If so, this is a Beta rv.

AND why don't you show your 'steps'?

3. Originally Posted by matheagle
IS 0<x<1? If so, this is a Beta rv.

AND why don't you show your 'steps'?
the range is not given ......

so i let the density function = K(1-x)^4 ,(where K is a constant)
and integrate it from -∞ to ∞, which is supposed to be equal to 1.

however, the result is undecisive after the integration,
so i cant find the constant K....

4. You need to know the support and I'd bet it's 0<x<1.
The support is not all Reals.

5. Originally Posted by matheagle
You need to know the support and I'd bet it's 0<x<1.
The support is not all Reals.

if your guess is true , it will be simple...
any reasons why u bet it's 0<x<1...?