A note on neighborhoods of analytic functions having positive real part
Let P denote the set of all functions analytic in the unit disk D={z||z|<1} having the form p(z)=1+∑k=1∞pkzk with Re{p(z)}>0. For δ≥0, let Nδ(p) be those functions q(z)=1+∑k=1∞qkzk analytic in D with ∑k=1∞|pk−qk|≤δ. We denote by P′ the class of functions analytic in D having the form p(z)=1+∑k...
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| Format: | Article |
| Language: | English |
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Hindawi Limited
1990-01-01
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| Series: | International Journal of Mathematics and Mathematical Sciences |
| Subjects: | |
| Online Access: | http://dx.doi.org/10.1155/S0161171290000643 |