Let $Y$ be a metric space and $H \subseteq C(X,Y)$ equicontinuous. Then the closure of $H$ is equicontinuous too.

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Let $(X, \mathcal{T})$ be a topological space, $(Y,d)$ be a metric space, and $H \subseteq C(X,Y)$. Then, $\operatorname{cl}(H)$ is equicontinuous too in the pointwise topology (subspace on the product topology $Y^X$).

My attempt:

We want to prove that $\operatorname{cl}(H)$ is equicontinuous in $x \in X$/

Let $\epsilon > 0$. Choose $V \in \mathcal{V}_X(x)$ open such that for all $f \in H: f(V) \subseteq B_d(f(x), \epsilon)$.

Then, we have to find $W \in \mathcal{V}_X(x)$ such that $f(V) \subseteq B_d(f(x), \epsilon)$ $\forall f \in \operatorname{cl}(H)$.

How do I proceed?

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Let $p \in X$ and $\varepsilon > 0$ be given. By equicontinuity, pick $V_p$, an open neighbourhood of $p$ such that

$$\forall h \in H: h[V_p] \subseteq B_d(h(p), \frac{\varepsilon}{3})$$

I claim that this $V_p$ also works for showing the equicontinuity of $\overline{H}$ (the pointwise closure of $H$ in $Y^X$) for $\varepsilon >0$, and to this end we let $f$ be any function in $\overline{H}$ and we I'll show that $$f[V_p] \subseteq B_d(f(p), \varepsilon)$$

and to this end, let $x \in V_p$ be arbitrary. (it's fixed for now.) Then define $$O = (\pi_x)^{-1}[B_d(f(x),\frac{\varepsilon}{3})] \cap (\pi_{p})^{-1}[B_d(f(p), \frac{\varepsilon}{3})]$$

which is an open subset of $Y^X$ in the product topology (which makes all $\pi_q, q \in X$ continuous,in particular $\pi_x$ and $\pi_p$, so $O$ is a finite intersection of two open sets of $Y^X$, hence open). By definition $f \in O$, and as $f \in \overline{H}$, there is some $h_0 \in H$ with $h_0 \in O$.

The last fact implies that $d(h_0(x), f(x)) < \frac{\varepsilon}{3}$ and also that $d(h_0(p), f(p)) < \frac{\varepsilon}{3}$ from the definitions. Also, $h_0 \in H$ implies that $$h_0[V_p] \subseteq B(h_0(p), \frac{\varepsilon}{3})$$

So: $$d(f(p),f(x)) < d(f(p), h_0(p)) + d(h_0(p), h_0(x)) + d(h_0(x), f(x)) < \frac{\varepsilon}{3} + \frac{\varepsilon}{3} + \frac{\varepsilon}{3} = \varepsilon$$

where the two outer inequalities are from $h_0 \in O$ and the middle from the equicontinuity and $x \in V_p$.

As $x \in V_p$ was arbitary, we have indeed shown $f[V_p] \subseteq B_d(f(p),\varepsilon)$, as was required.