- #1
Mattofix
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my question is regarding 'continuous' cumulative distribution functions.
i kind of get it apart from that darn 't' in the definition (see http://upload.wikimedia.org/math/f/2/4/f24252ffb5e5e747b246189b7e1cfcce.png). My textbook, my lecture notes and even wikipedia don't refrer to the 't', apart from in the definition. I wouldn't mind apart from that i am working my way through some questions and have come across quite a few
asking me for the 'c.d.f of X for all t' (for example t<0 and t>2), not asking for the c.d.f of x values (like all of the worked examples i have come across) so what are the questions after?
Here is an example so you understand what my problem is.
'X is a continuous random quantity with probability density function f(x) = x for 0<x<1, f(x)=2-x for 1 [tex]\leq[/tex] x < 2 with f(x)=0
for all other x. Find the value of Fx(t), the cumulative distribution function of X, for all t (that is t<0 and t>2 as well as 0 [tex]\leq[/tex] t [tex]\leq[/tex] 2 )'
http://upload.wikimedia.org/math/f/2/4/f24252ffb5e5e747b246189b7e1cfcce.png
http://upload.wikimedia.org/math/f/d/e/fdec25ee8674e78b0bad557daa923a41.png (maybe for when i find the new boundaries they are asking for?)
If it was like all of the examples iv seen id say for x<0 F(x)=0, for x>2 F(x)=1, for 0<x<1 F(x)= x[tex]^{2}[/tex]/2 and for 1<x<2 F(x)= 2x - x[tex]^{2}[/tex]/2 , but its not...
i kind of get it apart from that darn 't' in the definition (see http://upload.wikimedia.org/math/f/2/4/f24252ffb5e5e747b246189b7e1cfcce.png). My textbook, my lecture notes and even wikipedia don't refrer to the 't', apart from in the definition. I wouldn't mind apart from that i am working my way through some questions and have come across quite a few
asking me for the 'c.d.f of X for all t' (for example t<0 and t>2), not asking for the c.d.f of x values (like all of the worked examples i have come across) so what are the questions after?
Here is an example so you understand what my problem is.
Homework Statement
'X is a continuous random quantity with probability density function f(x) = x for 0<x<1, f(x)=2-x for 1 [tex]\leq[/tex] x < 2 with f(x)=0
for all other x. Find the value of Fx(t), the cumulative distribution function of X, for all t (that is t<0 and t>2 as well as 0 [tex]\leq[/tex] t [tex]\leq[/tex] 2 )'
Homework Equations
http://upload.wikimedia.org/math/f/2/4/f24252ffb5e5e747b246189b7e1cfcce.png
http://upload.wikimedia.org/math/f/d/e/fdec25ee8674e78b0bad557daa923a41.png (maybe for when i find the new boundaries they are asking for?)
The Attempt at a Solution
If it was like all of the examples iv seen id say for x<0 F(x)=0, for x>2 F(x)=1, for 0<x<1 F(x)= x[tex]^{2}[/tex]/2 and for 1<x<2 F(x)= 2x - x[tex]^{2}[/tex]/2 , but its not...