📘 set theory and algebra

1. **Problem statement:** Given sets $E$ and $F$ with $n(\xi) = 50$, $n(E) = 15$, $n(F) = 9$, and $n((E \cup F)') = 33$, find: (i) $n(E \cap F)$

1. **Find the power set of A = [a,b,c,d]** The power set of a set is the set of all possible subsets, including the empty set and the set itself.

1. Problem ক: Given $g(t) = \frac{t^4 + t^2 + 1}{t^2}$, find $g(-3^{-1})$. 2. To solve, note that $-3^{-1} = -\frac{1}{3}$.