The following could represent aprobability density function(p.d.f.) or not. If could, find the value of k.

How could I know it represent a p.d.f or not?

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- Nov 4th 2008, 08:18 PMgetonContinuous random variables – probability density functions
The following could represent a

**probability density function**(p.d.f.) or not. If could, find the value of k.

How could I know it represent a p.d.f or not? - Nov 4th 2008, 08:28 PMBlack Kawairothlite
evaluate if:

- Nov 4th 2008, 09:24 PMgeton
Well, my problem is not to finding k. I’ve confusion to recognize is it p.d.f or not.

If I try on this way,

f(-0.5) = k(0.75)

f(1) = 2k

I didn’t understand how the above info/working or else will show

**f(x) < 0. So it could not be a p.d.f.**(As my book’s answer.) - Nov 4th 2008, 09:29 PMgeton
If

So: k=3/2.

:confused::confused::confused: - Nov 4th 2008, 10:15 PMBlack Kawairothlite

you gotta "chop" the integral in three parts:

continue... - Nov 4th 2008, 10:19 PMBlack Kawairothlite
- Nov 4th 2008, 11:24 PMgeton
Answer:

**f(x) < 0.**

Therefore f(x) cannot be a probability density function.

- Nov 4th 2008, 11:26 PMmr fantastic
- Nov 5th 2008, 12:28 AMgeton
- Nov 5th 2008, 06:22 AMawkward
- Nov 6th 2008, 03:17 AMgeton