Applications of Ruscheweyh derivatives and Hadamard product to analytic functions
For given analytic functions ϕ(z)=z+∑m=2∞ λm zm,ψ(z)=z+∑m=2∞ μm zm in U={z||z|<1} with λm≥0,μm≥0 and λm≥μm, let En(ϕ,ψ;A,B) be the class of analytic functions f(z)=z+∑m=2∞am zm in U such that (f*Ψ)(z)≠0 and Dn+1(f*ϕ)(z)Dn(f*Ψ)(z)≪1+Az1+Bz, −1≤A<B≤1, z∈U, where Dnh(z)=z(zn−1h(z))(n)/n!, ...
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| Format: | Article |
| Language: | English |
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Hindawi Limited
1999-01-01
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| Series: | International Journal of Mathematics and Mathematical Sciences |
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| Online Access: | http://dx.doi.org/10.1155/S0161171299227950 |