Let R be an associative ring and a: R®R be an automorphism. A ring R is called quasi-Baer (respectively a- quasi-Baer), if the right annihilator of each ideal (respectively a- ideal ) of R, is generated by an idempotent, as an ideal of R.
In this project we study the skew polynomial ring R[x;a] and show that, when R[x;a] is a semiprime ring, then R[x;a] is quasi-Baer if R is an a- quasi-Baer ring.