Sufficient conditions for Janowski starlike functions with fixed second coefficient
Let $$A, B, D, E \in [-1,1]$$ and let p(z) be an analytic function with fixed initial coefficient defined in the open unit disk. Conditions on A, B, D, and E are determined so that $$1+ \alpha z p'(z)$$ being subordinated to $$(1+Dz)/(1+Ez)$$ implies that p(z) is subordinated to $$(1+Az)/(1+Bz)$$ and other similar implications involving $$1+ \alpha z p'(z)/p(z)$$ , $$\alpha p^2(z) + \lambda z p'(z) $$ , $$ \alpha p(z) + (1-\alpha ) p^2(z) + \lambda z p'(z)$$ , and $$ (1-\alpha ) p(z) + \alpha \left( 1+ z p'(z)/p(z) \right) $$ . Also, sufficient conditions for Janowski starlikeness with fixed second coefficient are obtained.
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