Hi Tutku,
The requirements documentation and requirements traceability matrix are considered project documents (see page 89 of the PMBOK® Guide). Project documents typically do not require an approved change request to make modifications. Therefore, it is not likely that these documents would be included in a change request. Page 120 of the PMBOK® Guide states that, "Any formally controlled project document may be updated as the result of this process." So, although not typical, if any of the project documents that have been placed under configuration control need to be changed, they would be updated as part of the Perform Integrated Change Control process. The change log is also a project document that is specifically mentioned as being updated during this process simply because it must be updated with the disposition of the change request.
