Hello,
No, you're all correct !
Note : please next time, put your attachments as .jpg, not .bmp, as it's more painful to open !
Cool Thanks so much! Im glad i was on the right track.
Does that same idea hold for when Im getting the marginal function of X
I get 2x^2 / 25 + 10/25 which is getting X over all values of Y where Y can be 1 or 3.
But is it also possible say for x = 1 and y = 50 for example which would still give a value for X even though the joint would give 0?
Perhaps it'll be clearer if you see it written this way :
Let be the domain of X, namely {1,2}
Let be the domain of Y, namely {1,3}
Then for any , we have :
Which exactly gives what you got :
if x is in2x^2 / 25 + 10/25
If , we still have , but then these values are 0, according to the definition of P(.,.)