The Booth Lemniscate Starlikeness Radius for Janowski Starlike Functions

The function G_\alpha(z)=1+ z/(1-\alpha z^2), \, 0\leq \alpha <1, maps the open unit disc \mathbb{D} onto the interior of a domain known as the Booth lemniscate. Associated with this function G_\alpha is the recently introduced class \mathcal{BS}(\alpha) consisting of normalized analytic functions f on \mathbb{D} satisfying the subordination $zf'(z)/f(z) \prec... Show more