Second Hankel determinant for tilted bi-starlike functions of order β

Let f be analytic in the unit disk D ={ z ∈ C : | z | < 1}, and S be the subclass of normalized univalent functions in D . We define the class of tilted bi-starlike functions S σ * ( β , δ ) , which satisfy the condition Re { e i δ [ z f ' ( z ) f ( z ) ] } > β where | δ | β . The second Hankel determinant | a 2 a 4 − a 3 2 | has been determined for S σ * ( β , δ ) . In this paper, we also found the coefficients bound for | a 2 |, | a 3 | and | a 4 |.