Heine–Borel TheoremTheoremA subset of Euclidean space $\mathbb{R}^n$ is compact if and only if it is closed and bounded.
Bolzano–Weierstrass TheoremTheoremEvery bounded sequence in $\mathbb{R}^n$ has a convergent subsequence.
Monotone Convergence TheoremTheoremIf a sequence of real numbers is monotone and bounded, then the sequence is convergent.
Fubini's TheoremTheoremIf a function is integrable on the product space, the double integral is equal to the iterated integrals.
Intermediate Value TheoremTheoremIf $f$ is a continuous function on $[a, b]$ and $u$ is a value between $f(a)$ and $f(b)$, then there exists a $c \in [a, b]$ such that $f(c) = u$.
Extreme Value TheoremTheoremA continuous real-valued function on a closed and bounded interval attains both a maximum and a minimum value.