Recent content by hocuspocus102

ok. Thank you very much!

that's what I think

so Y_f is just X?

it should

{1,2,3} are in Y_f because f(1) implies 1 is in it, f(2) implies 2 is in it and f(3) implies 3 is in it right?

ohhhh. ok so Y_f is whatever value you plug in for x?

no it's not

I don't know I thought f just took n to a set with all elements of X not including n because Y_f is x not in f(x)

I get that for f(1), 2 is in Y_f and 3 is in Y_f but 1 is not. for f(2), 1 is in Y_f and 3 is in Y_f but 2 is not. so for f(n) on a set of size t Y_f will have all numbers in the set 1 through t not including n in it. is that how you'd say that or is there a more explicit formula?

no 1 isn't in it because it's x in X such that x not in f(x) and 1 is not in f(1)

no, so is Yf just X/x ?

f(1) in that case would be {2,3} right? but how does that translate to Yf?

Homework Statement Suppose X is a non-empty set and f:X->power set of X (ie P(X)) is defined f(x) = X/x. Consider the subset Yf = {x in X such that x not in f(x)} of X. Determine Yf for the particular f we have just described. Homework Equations The Attempt at a Solution Any...

oh ok, thank you very much!

no, it only gives examples of how to use 2 different eigenvalues with their corresponding 2 different eigenvectors. is there a different way to do it?