Should the personal/research statement be technical? Related: Choosing research ideas to include in a statement of purpose

I know I must describe my past and current research in my personal/research statement or statement of purpose. But do I use technical terms?

I was given the advice that since the people reading my statement are mathematicians (I am applying to US for applied mathematics), they should know what I am talking about.

Although I am applying to applied mathematics, it would also be nice to hear from other fields (biology, computer science, engineering etc) about this.
At least in computer science: Yes, but.

What admissions committees are looking for in your application is strong evidence of research potential.  One of the indicators of research potential is the ability to write about your chosen field in its native language; not just technical terms, but their proper usage and context.  In particular, if you are describing your past research results, or a particular future research problem, you should describe it just as any professional researcher would.

However, there is technical language and technical language, and you want the former.  The vast majority of your statements should be understandable to a general audience of (in your case) applied mathematicians, not just to experts in your chosen subsubsubfield.  For the really technical details, cite the literature or point to your own work on your web page.  (The ability to effectively explain your research to non-experts, demonstrated knowledge of the literature, and willingness to embarrass yourself in public by posting your work to the web are also strong indicators of research potential.)