The Latex-text will not be represented as formulas. The Latex-text will not be rendered. Why? My text begins with 2 Dollar signs and ends with 2 Dollarsigns.
The problem was that there were blank/empty lines in your "formula."
I removed them. Now it renders.
That said, to use MathJax in this form is not ideal. It is better to write the text outside the math environment, and to include only the actual formulas in dollar symbols.