powerset

Let X be a set and 2$$^X$$ denote the powerset of X. Define a binary operation $$\Delta$$ on 2$$^X$$ as follows: $$A\Delta B=(A-B)\cup(B-A)$$. Let $$H=(2^X,\Delta)$$. Which of the...

Let $$U = \{ 1,2,3\} $$. Let 2$$^U$$ denote the powerset of U. Consider an undirected graph G whose vertex set is 2$$^U$$. For any $$A,B \in {2^U},(A,B)$$ is an edge in G if and on...

Let $$X,. Y, Z$$ be sets of sizes $$x, y$$ and $$z$$ respectively. Let $$W = X x Y$$ and $$E$$ be the set of all subjects of $$W$$. The number of functions from $$Z$$ to $$E$$ is