%0 Journal Article %T Normal Criteria and Shared Values by Differential Polynomials %A Jihong Wang %A Qian Lu %A Qilong Liao %J Advances in Pure Mathematics %P 210-217 %@ 2160-0384 %D 2011 %I Scientific Research Publishing %R 10.4236/apm.2011.14037 %X For a family of meromorphic functions on a domain D, it is discussed whether F is normal on D if for every pair functions <i>f</i>(z),<i>g</i>¡Ê<i>F</i> , <i>f</i>'¨C<i>af</i><sup>n</sup>and <i>g</i>'¨C<i>ag</i><sup>n</sup> share value <i>d</i> on D when n=2,3, where <i>a, b</i> are two complex numbers, <i>a</i>¡Ù0,¡Þ,<i>b</i>¡Ù¡Þ.Finally, the following result is obtained:Let <i>F</i> be a family of meromorphic functions in D, all of whose poles have multiplicity at least 4 , all of whose zeros have multiplicity at least 2. Suppose that there exist two functions <i>a</i>(z) not idendtically equal to zero, <i>d</i>(z) analytic in D, such that for each pair of functions <i>f</i> and in <i>F</i> , <i>f</i>'¨C<i>a</i>(z)<i>f</i><sup>2</sup> and <i>g</i>'¨C<i>a</i>(z)<i>g</i><sup>2</sup> share the function <i>d</i>(z) . If <i>a</i>(z) has only a multiple zeros and <i>f</i>(z)¡Ù¡Þ whenever <i>a</i>(z)=0 , then <i>F</i> is normal in D. %K Normal Family %K Meromorphic Function %K Shared Value %K Differential Polynomial %U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=6486