Test equations

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To blog math posts, I need to write equations. Lots of equations.
I found this page: https://www.quora.com/How-can-you-write-math-equations-on-Blogger-or-Blogspot. Then, I did what this page said.

An inline equation should be here \(e^{i\theta} = \cos\theta + i\sin\theta\).... And a display equation should be below: \begin{equation}e^{i\pi} = -1\end{equation} and so on.

Can I write equations like this? \(e^x = 1 + x + \cdots\)

Here are sets of numbers.
\begin{equation} \mathbb{N}, \mathbb{Z}, \mathbb{Q}, \mathbb{R}, \mathbb{C} \end{equation}

Vectors and matrices \begin{equation} \begin{pmatrix} 1\\ 2\\ 3\\ \vdots\\ n \end{pmatrix} \end{equation} \begin{equation} \begin{bmatrix} a_{11} & a_{12} & \cdots & a_{1n}\\ a_{21} & a_{22} & \cdots & a_{2n} \\ \vdots & \vdots & \ddots & \vdots \\ a_{n1} & a_{n2} & \cdots & a_{nn} \end{bmatrix} \end{equation}

Looks good!

$a+b=c$

`a + b = c`

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