# Extract the divergent/bounded part of a certain expression

Consider I have a power series which is function of $x$. A part of this expression is bounded when $x->\infty$, some remainder is on the other hand divergent when $x$ goes to infinity. What is the simplest way to extract out of my expression only the bounded part?

• I believe you're talking about a power Series. Otherwise you can always manipulate any expression to have as many "divergent" parts as you want cancelling out themselves when you add them up – Dr. belisarius Mar 5 '15 at 22:05
• Sure, sorry for the misunderstanding. – usumdelphini Mar 5 '15 at 22:07
• One place to start might be Series[func, {x,Infinity,1}]. If the divergent part is of polynomial or similar growth this might capture it. – Daniel Lichtblau Mar 5 '15 at 23:59