EMBLEM writes as if the matter were definitively resolved, but the honest answer is that noone knows. If dynamic linking makes a derivative work, then you are indeed required to publish your code under the GPL. If it doesn't, then you may publish your code under any licence you like; moreover, you may distribute the GPL library along with your application as mere aggregation, provided that you comply with the GPL's obligations with respect to the GPL library.
Whether dynamic linking makes a derivative work is, of course, the important question. My earlier answer here addresses the question in more detail, but the upshot was - and remains - that until courts of significance start ruling on this issue, we don't know for sure what constitutes a derivative work.
FAOD, let me be clear: I think the GPL is a good licence, and you will certainly simplify your position - and enrich humanity - if you decide to licence your work under the GPL also. But whether you are required to do so is not yet as cut-and-dried as some would have you believe.