# Display Math Equation in Post

There will be many posts demostrate how to transfer the mathematical laws to the codes, and the reversed flaw. I start from this famous equation:

\[ E = mc^2 \]

Use the steps 1 and 2 indtroducted in Fong Chun Chan’s post, my website is able to show the equation in any post. Because this theme use `kramdown`

as the engine of markdown, I pass the step 4.

Here are the proof the central limitation theorem. Mix of inline and one-line equations.

We have a sequence of independent random variables,\[ X_1, X_2, \ldots \]

And the mean and variance of them:

Mean \[ E \left[{X_i}\right] = \mu \in \left({-\infty \,.\,.\, \infty}\right) \]

Variance \[ V \left({X_i}\right) = \sigma^2 > 0 \]

Assume:

\[ S_n = \sum_{i \mathop = 1}^n X_i \]

Then:

\[ \displaystyle \frac {S_n - n \mu} {\sqrt {n \sigma^2} } \xrightarrow {D} N \left({0, 1}\right)\] as \[ n \to \infty \]

Embedded tex codes in `$$ ... $$`

, the equation was transfered inline or in single line. Thus I pass the step 3 of Fong Chun Chan’s method.

**Note.** Justify the last equation in 2020-01-30 18:30:09