I have two questions about the attached problem
\[E(XY)= \sum_{x,y}^{} xy f(x,y) = 29/18 \] how does he calculated it and answered it 29/18 and the second question is that how does he calculated the values in red box (in table) ????????
@TuringTest @experimentX @satellite73 any clue?
lol here is a tedious numerical example!
I am stuck at numerical calculation of this example I don't understand how does he calculated it
you just have to grind it til you find it that is why it is tedious
\[\sum_{x,y}xyf(x,y)\] means sum over all possible pairs
how?
so we can begin to compute. for example if \(x=1,y=-1\) you get \[1\times (-1)\times \frac{1}{18}=-\frac{1}{18}\]\]
can we do it like \[\sum_{x}^{?} xf(x) \sum_{y}^{?}yf(y)\] ?????
nope
ok, but in table it's 1/18 not -1/18
you have to do what is says and you have \(3\times 3=9\) products to consider
ok lets go slow
\[f(1,-1)=\frac{1}{18}\] from the table right?
how did you calculate it~?
i didn't i looked in the table under the appropriate slot
but it should be -1/18 why is it 1/18 in the table is it some printing mistake?
|dw:1338134141940:dw|
Join our real-time social learning platform and learn together with your friends!