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Cos




Mathematica Notation

Traditional Notation









Elementary Functions > Cos[z] > Representations through more general functions > Through other functions > Involving Bessel functions





http://functions.wolfram.com/01.07.26.0065.01









  


  








Input Form





Cos[z] == Sqrt[(I z)/(2 Pi)] BesselK[-(1/2), I z] + Sqrt[-((I z)/(2 Pi))] BesselK[-(1/2), (-I) z]








Standard Form





Cell[BoxData[RowBox[List[RowBox[List["Cos", "[", "z", "]"]], "\[Equal]", RowBox[List[RowBox[List[SqrtBox[FractionBox[RowBox[List[" ", RowBox[List["\[ImaginaryI]", " ", "z"]]]], RowBox[List["2", "\[Pi]"]]]], " ", RowBox[List["BesselK", "[", RowBox[List[RowBox[List["-", FractionBox["1", "2"]]], ",", RowBox[List["\[ImaginaryI]", " ", "z"]]]], "]"]]]], "+", RowBox[List[SqrtBox[RowBox[List["-", FractionBox[RowBox[List["\[ImaginaryI]", " ", "z"]], RowBox[List["2", "\[Pi]"]]]]]], " ", RowBox[List["BesselK", "[", RowBox[List[RowBox[List["-", FractionBox["1", "2"]]], ",", RowBox[List[RowBox[List["-", "\[ImaginaryI]"]], " ", "z"]]]], "]"]]]]]]]]]]








MathML Form







<math xmlns='http://www.w3.org/1998/Math/MathML' mathematica:form='TraditionalForm' xmlns:mathematica='http://www.wolfram.com/XML/'> <semantics> <mrow> <mrow> <mi> cos </mi> <mo> &#8289; </mo> <mo> ( </mo> <mi> z </mi> <mo> ) </mo> </mrow> <mo> &#10869; </mo> <mrow> <mrow> <msqrt> <mrow> <mo> - </mo> <mfrac> <mrow> <mi> &#8520; </mi> <mo> &#8290; </mo> <mi> z </mi> </mrow> <mrow> <mn> 2 </mn> <mo> &#8290; </mo> <mi> &#960; </mi> </mrow> </mfrac> </mrow> </msqrt> <mo> &#8290; </mo> <mrow> <msub> <mi> K </mi> <mrow> <mo> - </mo> <mfrac> <mn> 1 </mn> <mn> 2 </mn> </mfrac> </mrow> </msub> <mo> ( </mo> <mrow> <mrow> <mo> - </mo> <mi> &#8520; </mi> </mrow> <mo> &#8290; </mo> <mi> z </mi> </mrow> <mo> ) </mo> </mrow> </mrow> <mo> + </mo> <mrow> <msqrt> <mfrac> <mrow> <mi> &#8520; </mi> <mo> &#8290; </mo> <mi> z </mi> </mrow> <mrow> <mn> 2 </mn> <mo> &#8290; </mo> <mi> &#960; </mi> </mrow> </mfrac> </msqrt> <mo> &#8290; </mo> <mrow> <msub> <mi> K </mi> <mrow> <mo> - </mo> <mfrac> <mn> 1 </mn> <mn> 2 </mn> </mfrac> </mrow> </msub> <mo> ( </mo> <mrow> <mi> &#8520; </mi> <mo> &#8290; </mo> <mi> z </mi> </mrow> <mo> ) </mo> </mrow> </mrow> </mrow> </mrow> <annotation-xml encoding='MathML-Content'> <apply> <eq /> <apply> <cos /> <ci> z </ci> </apply> <apply> <plus /> <apply> <times /> <apply> <power /> <apply> <times /> <cn type='integer'> -1 </cn> <apply> <times /> <imaginaryi /> <ci> z </ci> <apply> <power /> <apply> <times /> <cn type='integer'> 2 </cn> <pi /> </apply> <cn type='integer'> -1 </cn> </apply> </apply> </apply> <cn type='rational'> 1 <sep /> 2 </cn> </apply> <apply> <ci> BesselK </ci> <apply> <times /> <cn type='integer'> -1 </cn> <cn type='rational'> 1 <sep /> 2 </cn> </apply> <apply> <times /> <apply> <times /> <cn type='integer'> -1 </cn> <imaginaryi /> </apply> <ci> z </ci> </apply> </apply> </apply> <apply> <times /> <apply> <power /> <apply> <times /> <imaginaryi /> <ci> z </ci> <apply> <power /> <apply> <times /> <cn type='integer'> 2 </cn> <pi /> </apply> <cn type='integer'> -1 </cn> </apply> </apply> <cn type='rational'> 1 <sep /> 2 </cn> </apply> <apply> <ci> BesselK </ci> <apply> <times /> <cn type='integer'> -1 </cn> <cn type='rational'> 1 <sep /> 2 </cn> </apply> <apply> <times /> <imaginaryi /> <ci> z </ci> </apply> </apply> </apply> </apply> </apply> </annotation-xml> </semantics> </math>










Rule Form





Cell[BoxData[RowBox[List[RowBox[List["HoldPattern", "[", RowBox[List["Cos", "[", "z_", "]"]], "]"]], "\[RuleDelayed]", RowBox[List[RowBox[List[SqrtBox[FractionBox[RowBox[List["\[ImaginaryI]", " ", "z"]], RowBox[List["2", " ", "\[Pi]"]]]], " ", RowBox[List["BesselK", "[", RowBox[List[RowBox[List["-", FractionBox["1", "2"]]], ",", RowBox[List["\[ImaginaryI]", " ", "z"]]]], "]"]]]], "+", RowBox[List[SqrtBox[RowBox[List["-", FractionBox[RowBox[List["\[ImaginaryI]", " ", "z"]], RowBox[List["2", " ", "\[Pi]"]]]]]], " ", RowBox[List["BesselK", "[", RowBox[List[RowBox[List["-", FractionBox["1", "2"]]], ",", RowBox[List[RowBox[List["-", "\[ImaginaryI]"]], " ", "z"]]]], "]"]]]]]]]]]]


Date Added to functions.wolfram.com (modification date)





2001-10-29