Typo fixes.

This commit is contained in:
Bokuan Li
2026-03-15 12:32:31 -04:00
parent f951ccccdf
commit 62a8e78dfe
3 changed files with 29 additions and 18 deletions

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@@ -35,26 +35,33 @@
A(h, k) &= Df(x + h)(k) + Df(x)(k) \\ A(h, k) &= Df(x + h)(k) + Df(x)(k) \\
&+ [f(x + h + k) - f(x + h) - Df(x + h)(k)] \\ &+ [f(x + h + k) - f(x + h) - Df(x + h)(k)] \\
&- [f(x + k) - f(x) - Df(x)(k)] \\ &- [f(x + k) - f(x) - Df(x)(k)] \\
&= D^2f(x)(h, k) + r_1(h) \cdot Df(x)(k) &= D^2f(x)(h, k) + r_1(h) \cdot Df(x)(k) \\
&+ [f(x + h + k) - f(x + h) - Df(x + h)(k)] \\ &+ [f(x + h + k) - f(x + h) - Df(x + h)(k)] \\
&- [f(x + k) - f(x) - Df(x)(k)] \\ &- [f(x + k) - f(x) - Df(x)(k)] \\
\end{align*} \end{align*}
Let $B_h: B_E(0, r) \to F$ be defined by Let $B_h: B_E(0, r) \to F$ be defined by
\[ \begin{align*}
B_h(k) = f(x + h + k) - f(x + k) - Df(x + h)(k) + Df(x)(k) B_h(k) &= f(x + h + k) - f(x + k) \\
\] &- Df(x + h)(k) + Df(x)(k)
\end{align*}
then then
\[ \begin{align*}
B_h(k) - B_h(0) = f(x + h + k) - f(x + k) - Df(x + h)(k) + Df(x)(k) -f(x + h) + f(x) B_h(k) - B_h(0) &= f(x + h + k) - f(x + k) \\
\] &- Df(x + h)(k) + Df(x)(k) \\
&-f(x + h) + f(x)
\end{align*}
Now, there exists $r_2, r_3 \in \mathcal{R}_{B(E)}$ such that for any $k \in B(0, r)$, Now, there exists $r_2, r_3 \in \mathcal{R}_{B(E)}$ such that for any $k \in B(0, r)$,
\begin{align*} \begin{align*}
DB_h(k) &= Df(x + h + k) - Df(x + k) - Df(x + h) + Df(x) \\ DB_h(k) &= Df(x + h + k) - Df(x + k) - Df(x + h) + Df(x) \\
&= D^2f(x)(h + k) + Df(x) - D^2f(x)(h) - Df(x) - D^2f(x)(k) + r_2(k) + r_3(h) \\ &= D^2f(x)(h + k) + Df(x) - D^2f(x)(h) \\
&- Df(x) - D^2f(x)(k) + r_2(k) + r_3(h) \\
&=r_2(k) + r_3(h) &=r_2(k) + r_3(h)
\end{align*} \end{align*}
By the \hyperref[Mean Value Theorem]{theorem:mean-value-theorem}, By the \hyperref[Mean Value Theorem]{theorem:mean-value-theorem},
\[ \[
\norm{B_h(k) - B_h(0)}_F \le \norm{k}_E \cdot o(\norm{k}_E + \norm{h}_E) \norm{B_h(k) - B_h(0)}_F \le \norm{k}_E \cdot o(\norm{k}_E + \norm{h}_E)
@@ -68,9 +75,12 @@
so $D^2f(x)(h, k) - D^2f(x)(k, h) = 0$. so $D^2f(x)(h, k) - D^2f(x)(k, h) = 0$.
Now suppose that the proposition holds for $n$. Identify $L^n(E; F) = L^{2}(E; L^{n-2}(E; F))$, then for any $\seqf[n]{x_j} \subset E$, Now suppose that the proposition holds for $n$. Identify $L^n(E; F) = L^{2}(E; L^{n-2}(E; F))$, then for any $\seqf[n]{x_j} \subset E$,
\[ \begin{align*}
Df(x)(x_1, \cdots, x_n) = Df(x)(x_1, x_2)(x_3, \cdots, x_n) = Df(x)(x_2, x_1)(x_3, \cdots, x_n) = Df(x)(x_2, x_1, x_3, \cdots, x_n) Df(x)(x_1, \cdots, x_n) &= Df(x)(x_1, x_2)(x_3, \cdots, x_n) \\
\] &= Df(x)(x_2, x_1)(x_3, \cdots, x_n) \\
&= Df(x)(x_2, x_1, x_3, \cdots, x_n)
\end{align*}
Since any element $\sigma \in S_n$ that does not fix $x_1$ is the composition of the transposition $(12)$ and an element that fixes $x_1$, $Df(x)$ is symmetric. Since any element $\sigma \in S_n$ that does not fix $x_1$ is the composition of the transposition $(12)$ and an element that fixes $x_1$, $Df(x)$ is symmetric.
\end{proof} \end{proof}

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@@ -5,7 +5,7 @@
\label{definition:vanish-at-infinity} \label{definition:vanish-at-infinity}
Let $X$ be a topological space, $E$ be a TVS over $K \in \RC$, and $f \in C(X; E)$, then $f$ \textbf{vanishes at infinity} if for every $U \in \cn_E^o(0)$, $\bracs{f \not\in U}$ is compact. Let $X$ be a topological space, $E$ be a TVS over $K \in \RC$, and $f \in C(X; E)$, then $f$ \textbf{vanishes at infinity} if for every $U \in \cn_E^o(0)$, $\bracs{f \not\in U}$ is compact.
The set $C_0(X; \complex)$ is the space of all functions that vanish at infinity. The set $C_0(X; E)$ is the space of all functions that vanish at infinity.
\end{definition} \end{definition}
\begin{proposition} \begin{proposition}

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@@ -70,14 +70,15 @@ The axioms of uniform spaces strongly resembles working in a metric space. In fa
\begin{enumerate} \begin{enumerate}
\item[(FB1)] For any $J, J' \subset I$ finite and $r, r' > 0$, \item[(FB1)] For any $J, J' \subset I$ finite and $r, r' > 0$,
\[ \[
\bigcap_{j \in J \cup J'}E(d_j, \min(r,r')E(d_j, r \wedge r') \subset \paren{\bigcap_{j \in J}E(d_j, r)} \cap \paren{\bigcap_{j \in J'}E(d_j, r')} \bigcap_{j \in J \cup J'}E(d_j, r \wedge r') \subset \paren{\bigcap_{j \in J}E(d_j, r)} \cap \paren{\bigcap_{j \in J'}E(d_j, r')}
\] \]
\item[(UB1)] For each $i \in I$, $d(x, x) = 0$ for all $x \in X$. Thus for any $i \in I$ and $r > 0$, $E(d_i, r)$ contains the diagonal. \item[(UB1)] For each $i \in I$, $d(x, x) = 0$ for all $x \in X$. Thus for any $i \in I$ and $r > 0$, $E(d_i, r)$ contains the diagonal.
\item[(UB2)] For each $J \subset I$ finite and $r > 0$, \item[(UB2)] For each $J \subset I$ finite and $r > 0$,
\[ \begin{align*}
\paren{\bigcap_{j \in J}E(d_j, r/2)} \circ \paren{\bigcap_{j \in J}E(d_j, r)} \subset \bigcap_{j \in J}E(d_j, r/2) \circ E(d_j, r/2) \subset \bigcap_{j \in J}E(d_j, r) \paren{\bigcap_{j \in J}E(d_j, r/2)} \circ \paren{\bigcap_{j \in J}E(d_j, r)} &\subset \bigcap_{j \in J}E(d_j, r/2) \circ E(d_j, r/2) \\
\] &\subset \bigcap_{j \in J}E(d_j, r)
\end{align*}
by the triangle inequality. by the triangle inequality.
\end{enumerate} \end{enumerate}