## 1.6.12

### Section numbering with chapter in amsbook

I'm using amsbook to write a report. I'm using \chapter{}s and \section{}s, and their numbering is fine. However, \section{}s are numbered sequentially inside each \chapter{}, but without the indication of the \chapter{}: basically, I'm getting Section 1 instead of1.1, and similarly Subsection 1 instead of 1.1.1.
How do I go about fixing this?

Write the following in the preamble:
\renewcommand{\thesection}{\thechapter.\arabic{section}}


alternate approach: in the preamble,
\numberwithin{section}{chapter}

but it doesn't carry along to subsections; for that you'd need
\numberwithin{subsection}{section}

etc.