### Set LaTeX fontsize in labels?

The size of the text:

```
plot(sin, 0, pi, legend_label='$sin(x)$', fontsize=28)
plot(sin, 0, pi, legend_label='$sin(x)$').show(fontsize=28)
```

differs for the parts rendered using LaTeX (i.e. they are not affected by the fontsize size, $sin(x)$ is still a small text). How can I specify font for the LaTeX parts of the labels?