From the Exchange Management Console you may preview the recipients returned from the recipient filter applied to the dynamic distribution group.
It is also possible to do this from the Exchange Management Shell by invoking the Get-Recipient cmdlet agaisnt the recipient filter of the dynamic distribution group as below:
Get-Recipient -RecipientPreviewFilter (Get-DynamicDistributionGroup -Identity "<Dynamic Distrubution Group>").RecipientFilter | Select Name
For Example, to return the names of recipients that match the filter for the dynamic distribution group Sales:
Get-Recipient -RecipientPreviewFilter (Get-DynamicDistributionGroup -Identity "Sales").RecipientFilter | Select Name