Dimension of a scheme $X$ at a closed point $x$ and dimension of its local ring.

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The dimension of an irreducible scheme $X$ at $x$, dim$_x(X)$ is defined as the smallest dimension among its open neighbourhoods and the dimension of its local ring dim$(\mathcal{O}_{X,x})$ is just the Krull dimension.

There are many properties of those two dimensions, as well as the Krull dimension of a scheme dim$X$, and their relationships. For example, dim$X$=sup$_x$ dim$_x(X)$=dim$(\mathcal{O}_{X,x})$ for closed points $x$.

I am wondering

(1) if it is true that dim$_x(X)$=dim$(\mathcal{O}_{X,x})$ for a closed point $x$?

(2) And how to prove $\dim _ x(X) \geq \dim (\mathcal{O}_{X, x})$ in general? (I guess it is true...)

Thank you all in advance!