Equations and theorems numbered continuously within a chapter.

I want to have a continuous sharing of numbering for the equations AND the theorems in a chapter. I am using \documentclass{book}. For example, in chapter 2, I wish to get, say

Theorem 2.1

(equation numbered) (2.2)

Theorem 2.3 etc.

Any help will be appreciated. Thanks!

Re: Equations and theorems numbered continuously within a chapter.

I was able to do it this way finally.

\numberwithin{equation}{chapter}

\newtheorem{theorem}[equation]{Theorem}

\newtheorem{lemma}[equation]{Lemma} , etc

Thanks for everyone who read this post and thought about it. :)