Inline matrix display

I tried to write an inline matrix like this:

```markdown
Some text blah blah $\begin{bmatrix} a & b \\ c & d \end{bmatrix}$
```

However, the matrix was rendered to this:

```
[a   amp; b c  amp; d]
```

But the same code worked well for a block equation:

```
$$\begin{bmatrix} a & b \\ c & d \end{bmatrix}$$
```

Do anyone got any solutions?