Elementarna teoria mnogości

\(\newcommand{\footnotename}{footnote}\) \(\def \LWRfootnote {1}\) \(\newcommand {\footnote }[2][\LWRfootnote ]{{}^{\mathrm {#1}}}\) \(\newcommand {\footnotemark }[1][\LWRfootnote ]{{}^{\mathrm {#1}}}\) \(\newcommand \ensuremath [1]{#1}\) \(\newcommand {\LWRframebox }[2][]{\fbox {#2}} \newcommand {\framebox }[1][]{\LWRframebox } \) \(\newcommand {\setlength }[2]{}\) \(\newcommand {\addtolength }[2]{}\) \(\newcommand {\setcounter }[2]{}\) \(\newcommand {\addtocounter }[2]{}\) \(\newcommand {\cline }[1]{}\) \(\newcommand {\directlua }[1]{\text {(directlua)}}\) \(\newcommand {\luatexdirectlua }[1]{\text {(directlua)}}\) \(\newcommand {\protect }{}\) \(\def \LWRabsorbnumber #1 {}\) \(\def \LWRabsorbquotenumber "#1 {}\) \(\def \mathchar {\ifnextchar "\LWRabsorbquotenumber \LWRabsorbnumber }\) \(\def \mathcode #1={\mathchar }\) \(\let \delcode \mathcode \) \(\let \delimiter \mathchar \) \(\let \LWRref \ref \) \(\renewcommand {\ref }{\ifstar \LWRref \LWRref }\) \(\newcommand {\intertext }[1]{\text {#1}\notag \\}\) \(\let \emptyset \varnothing \) \(\let \ge \geqslant \) \(\let \le \leqslant \) \(\let \geq \geqslant \) \(\let \leq \leqslant \) \(\let \epsilon \varepsilon \) \(\let \eps \varepsilon \) \(\let \e \varepsilon \) \(\let \phi \varphi \) \(\let \bar \overline \) \(\let \hat \widehat \) \(\let \tilde \widetilde \) \(\let \eqnref \eqref \) \(\let \tensor \otimes \) \(\let \isom \cong \) \(\let \mapto \longrightarrow \) \(\let \lra \Longrightarrow \) \(\newcommand \bbP {\mathbb P}\) \(\newcommand \N {\mathbb N}\) \(\newcommand \Q {\mathbb Q}\) \(\newcommand \R {\mathbb R}\) \(\newcommand \Z {\mathbb Z}\) \(\def \field {\mathbb {K}}\) \(\def \PP {\mathbb {P}}\) \(\newcommand \calo {{\mathcal O}}\) \(\def \p {{\mathcal P}}\) \(\newcommand {\dvee }{\mathbin {\dot {\vee }}}\) \(\newcommand {\relR }{\mathbin {R}}\) \(\newcommand {\relRA }{\mathbin {R_A}}\) \(\renewenvironment {cases}{\left \{\begin {array}{@{}l@{\quad }l}}{\end {array}\right .}\) \(\newcommand \eqdef {\stackrel {\mbox {\scriptsize def}}{=}}\) \(\newcommand \bij {\begin {svg}\input {./eltm_ht_lwarp-images/bij.svg}\end {svg}}\) \(\newcommand \pto {\mathrel {\ooalign {\hfil $\mapstochar $\hfil \cr $\to $\cr }}}\) \(\newcommand \Dom {\operatorname {Dom}}\) \(\newcommand \tg {\operatorname {tg}}\) \(\newcommand \plz {ż}\)