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 | | http://functions.wolfram.com/01.20.27.0008.01 | 
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 | | Cosh[z] == Sqrt[1 - Sin[I z]^2] /; Abs[Im[z]] < Pi/2 | 
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 | | Cell[BoxData[RowBox[List[RowBox[List[RowBox[List["Cosh", "[", "z", "]"]], "\[Equal]", SqrtBox[RowBox[List["1", "-", SuperscriptBox[RowBox[List["Sin", "[", RowBox[List["\[ImaginaryI]", " ", "z"]], "]"]], "2"]]]]]], "/;", RowBox[List[RowBox[List["Abs", "[", RowBox[List["Im", "[", "z", "]"]], "]"]], "<", FractionBox["\[Pi]", "2"]]]]]]] | 
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   <math xmlns='http://www.w3.org/1998/Math/MathML' mathematica:form='TraditionalForm' xmlns:mathematica='http://www.wolfram.com/XML/'>  <semantics>  <mrow>  <mrow>  <mrow>  <mi> cosh </mi>  <mo> ⁡ </mo>  <mo> ( </mo>  <mi> z </mi>  <mo> ) </mo>  </mrow>  <mo> ⩵ </mo>  <msqrt>  <mrow>  <mn> 1 </mn>  <mo> - </mo>  <mrow>  <msup>  <mi> sin </mi>  <mn> 2 </mn>  </msup>  <mo> ( </mo>  <mrow>  <mi> ⅈ </mi>  <mo> ⁢ </mo>  <mi> z </mi>  </mrow>  <mo> ) </mo>  </mrow>  </mrow>  </msqrt>  </mrow>  <mo> /; </mo>  <mrow>  <mrow>  <semantics>  <mo> ❘ </mo>  <annotation encoding='Mathematica'> "\[LeftBracketingBar]" </annotation>  </semantics>  <mrow>  <mi> Im </mi>  <mo> ⁡ </mo>  <mo> ( </mo>  <mi> z </mi>  <mo> ) </mo>  </mrow>  <semantics>  <mo> ❘ </mo>  <annotation encoding='Mathematica'> "\[RightBracketingBar]" </annotation>  </semantics>  </mrow>  <mo> < </mo>  <mfrac>  <mi> π </mi>  <mn> 2 </mn>  </mfrac>  </mrow>  </mrow>  <annotation-xml encoding='MathML-Content'>  <apply>  <ci> Condition </ci>  <apply>  <eq />  <apply>  <cosh />  <ci> z </ci>  </apply>  <apply>  <power />  <apply>  <plus />  <cn type='integer'> 1 </cn>  <apply>  <times />  <cn type='integer'> -1 </cn>  <apply>  <power />  <apply>  <sin />  <apply>  <times />  <imaginaryi />  <ci> z </ci>  </apply>  </apply>  <cn type='integer'> 2 </cn>  </apply>  </apply>  </apply>  <cn type='rational'> 1 <sep /> 2 </cn>  </apply>  </apply>  <apply>  <lt />  <apply>  <abs />  <apply>  <imaginary />  <ci> z </ci>  </apply>  </apply>  <apply>  <times />  <pi />  <apply>  <power />  <cn type='integer'> 2 </cn>  <cn type='integer'> -1 </cn>  </apply>  </apply>  </apply>  </apply>  </annotation-xml>  </semantics>  </math> 
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 | | Cell[BoxData[RowBox[List[RowBox[List["HoldPattern", "[", RowBox[List["Cosh", "[", "z_", "]"]], "]"]], "\[RuleDelayed]", RowBox[List[SqrtBox[RowBox[List["1", "-", SuperscriptBox[RowBox[List["Sin", "[", RowBox[List["\[ImaginaryI]", " ", "z"]], "]"]], "2"]]]], "/;", RowBox[List[RowBox[List["Abs", "[", RowBox[List["Im", "[", "z", "]"]], "]"]], "<", FractionBox["\[Pi]", "2"]]]]]]]]] | 
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 | | Date Added to functions.wolfram.com (modification date) | 
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