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 | | http://functions.wolfram.com/01.26.27.1623.01 | 
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 | | ArcCosh[(2 z)/(z^2 + 1)] == (Sqrt[-(z - 1)^2]/(z - 1)) Sqrt[z + 1] 
   Sqrt[1/(z + 1)] (-2 I ArcTanh[I z] + (3 Pi)/2) /; 
 Abs[z] > 1 && (Inequality[Pi/2, Less, Arg[z], LessEqual, Pi] || 
   Inequality[-Pi, Less, Arg[z], LessEqual, -(Pi/2)]) | 
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 | | Cell[BoxData[RowBox[List[RowBox[List[RowBox[List["ArcCosh", "[", FractionBox[RowBox[List["2", " ", "z"]], RowBox[List[SuperscriptBox["z", "2"], "+", "1"]]], "]"]], "\[Equal]", RowBox[List[FractionBox[SqrtBox[RowBox[List["-", SuperscriptBox[RowBox[List["(", RowBox[List["z", "-", "1"]], ")"]], "2"]]]], RowBox[List["z", "-", "1"]]], " ", SqrtBox[RowBox[List["z", "+", "1"]]], SqrtBox[FractionBox["1", RowBox[List["z", "+", "1"]]]], RowBox[List["(", RowBox[List[RowBox[List[RowBox[List["-", "2"]], "\[ImaginaryI]", "  ", RowBox[List["ArcTanh", "[", RowBox[List["\[ImaginaryI]", " ", "z"]], "]"]]]], "+", FractionBox[RowBox[List["3", "\[Pi]"]], "2"]]], ")"]]]]]], "/;", RowBox[List[RowBox[List[RowBox[List["Abs", "[", "z", "]"]], ">", "1"]], "\[And]", RowBox[List["(", RowBox[List[RowBox[List[FractionBox["\[Pi]", "2"], "<", RowBox[List["Arg", "[", "z", "]"]], "\[LessEqual]", "\[Pi]"]], "\[Or]", RowBox[List[RowBox[List["-", "\[Pi]"]], "<", RowBox[List["Arg", "[", "z", "]"]], "\[LessEqual]", RowBox[List["-", 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>  <msup>  <mi> cosh </mi>  <mrow>  <mo> - </mo>  <mn> 1 </mn>  </mrow>  </msup>  <mo> ( </mo>  <mfrac>  <mrow>  <mn> 2 </mn>  <mo> ⁢ </mo>  <mi> z </mi>  </mrow>  <mrow>  <msup>  <mi> z </mi>  <mn> 2 </mn>  </msup>  <mo> + </mo>  <mn> 1 </mn>  </mrow>  </mfrac>  <mo> ) </mo>  </mrow>  <mo> ⩵ </mo>  <mrow>  <mfrac>  <mrow>  <msqrt>  <mrow>  <mo> - </mo>  <msup>  <mrow>  <mo> ( </mo>  <mrow>  <mi> z </mi>  <mo> - </mo>  <mn> 1 </mn>  </mrow>  <mo> ) </mo>  </mrow>  <mn> 2 </mn>  </msup>  </mrow>  </msqrt>  <mo> ⁢ </mo>  <msqrt>  <mrow>  <mi> z </mi>  <mo> + </mo>  <mn> 1 </mn>  </mrow>  </msqrt>  <mtext>   </mtext>  </mrow>  <mrow>  <mi> z </mi>  <mo> - </mo>  <mn> 1 </mn>  </mrow>  </mfrac>  <mo> ⁢ </mo>  <msqrt>  <mfrac>  <mn> 1 </mn>  <mrow>  <mi> z </mi>  <mo> + </mo>  <mn> 1 </mn>  </mrow>  </mfrac>  </msqrt>  <mo> ⁢ </mo>  <mrow>  <mo> ( </mo>  <mrow>  <mrow>  <mrow>  <mo> - </mo>  <mn> 2 </mn>  </mrow>  <mo> ⁢ </mo>  <mi> ⅈ </mi>  <mo> ⁢ </mo>  <mtext>    </mtext>  <mrow>  <msup>  <mi> tanh </mi>  <mrow>  <mo> - </mo>  <mn> 1 </mn>  </mrow>  </msup>  <mo> ( </mo>  <mrow>  <mi> ⅈ </mi>  <mo> ⁢ </mo>  <mi> z </mi>  </mrow>  <mo> ) </mo>  </mrow>  </mrow>  <mo> + </mo>  <mfrac>  <mrow>  <mn> 3 </mn>  <mo> ⁢ </mo>  <mi> π </mi>  </mrow>  <mn> 2 </mn>  </mfrac>  </mrow>  <mo> ) </mo>  </mrow>  </mrow>  </mrow>  <mo> /; </mo>  <mrow>  <mrow>  <mrow>  <semantics>  <mo> ❘ </mo>  <annotation encoding='Mathematica'> "\[LeftBracketingBar]" </annotation>  </semantics>  <mi> z </mi>  <semantics>  <mo> ❘ </mo>  <annotation encoding='Mathematica'> "\[RightBracketingBar]" </annotation>  </semantics>  </mrow>  <mo> > </mo>  <mn> 1 </mn>  </mrow>  <mo> ∧ </mo>  <mrow>  <mo> ( </mo>  <mrow>  <mrow>  <mfrac>  <mi> π </mi>  <mn> 2 </mn>  </mfrac>  <mo> < </mo>  <mrow>  <mi> arg </mi>  <mo> ⁡ </mo>  <mo> ( </mo>  <mi> z </mi>  <mo> ) </mo>  </mrow>  <mo> ≤ </mo>  <mi> π </mi>  </mrow>  <mo> ∨ </mo>  <mrow>  <mrow>  <mo> - </mo>  <mi> π </mi>  </mrow>  <mo> < </mo>  <mrow>  <mi> arg </mi>  <mo> ⁡ </mo>  <mo> ( </mo>  <mi> z </mi>  <mo> ) </mo>  </mrow>  <mo> ≤ </mo>  <mrow>  <mo> - </mo>  <mfrac>  <mi> π </mi>  <mn> 2 </mn>  </mfrac>  </mrow>  </mrow>  </mrow>  <mo> ) </mo>  </mrow>  </mrow>  </mrow>  <annotation-xml encoding='MathML-Content'>  <apply>  <ci> Condition </ci>  <apply>  <eq />  <apply>  <arccosh />  <apply>  <times />  <cn type='integer'> 2 </cn>  <ci> z </ci>  <apply>  <power />  <apply>  <plus />  <apply>  <power />  <ci> z </ci>  <cn type='integer'> 2 </cn>  </apply>  <cn type='integer'> 1 </cn>  </apply>  <cn type='integer'> -1 </cn>  </apply>  </apply>  </apply>  <apply>  <times />  <apply>  <times />  <apply>  <power />  <apply>  <times />  <cn type='integer'> -1 </cn>  <apply>  <power />  <apply>  <plus />  <ci> z </ci>  <cn type='integer'> -1 </cn>  </apply>  <cn type='integer'> 2 </cn>  </apply>  </apply>  <cn type='rational'> 1 <sep /> 2 </cn>  </apply>  <apply>  <power />  <apply>  <plus />  <ci> z </ci>  <cn type='integer'> 1 </cn>  </apply>  <cn type='rational'> 1 <sep /> 2 </cn>  </apply>  <apply>  <power />  <apply>  <plus />  <ci> z </ci>  <cn type='integer'> -1 </cn>  </apply>  <cn type='integer'> -1 </cn>  </apply>  </apply>  <apply>  <power />  <apply>  <times />  <cn type='integer'> 1 </cn>  <apply>  <power />  <apply>  <plus />  <ci> z </ci>  <cn type='integer'> 1 </cn>  </apply>  <cn type='integer'> -1 </cn>  </apply>  </apply>  <cn type='rational'> 1 <sep /> 2 </cn>  </apply>  <apply>  <plus />  <apply>  <times />  <cn type='integer'> -2 </cn>  <imaginaryi />  <apply>  <arctanh />  <apply>  <times />  <imaginaryi />  <ci> z </ci>  </apply>  </apply>  </apply>  <apply>  <times />  <cn type='integer'> 3 </cn>  <pi />  <apply>  <power />  <cn type='integer'> 2 </cn>  <cn type='integer'> -1 </cn>  </apply>  </apply>  </apply>  </apply>  </apply>  <apply>  <and />  <apply>  <gt />  <apply>  <abs />  <ci> z </ci>  </apply>  <cn type='integer'> 1 </cn>  </apply>  <apply>  <or />  <apply>  <ci> Inequality </ci>  <apply>  <times />  <pi />  <apply>  <power />  <cn type='integer'> 2 </cn>  <cn type='integer'> -1 </cn>  </apply>  </apply>  <lt />  <apply>  <arg />  <ci> z </ci>  </apply>  <leq />  <pi />  </apply>  <apply>  <ci> Inequality </ci>  <apply>  <times />  <cn type='integer'> -1 </cn>  <pi />  </apply>  <lt />  <apply>  <arg />  <ci> z </ci>  </apply>  <leq />  <apply>  <times />  <cn type='integer'> -1 </cn>  <apply>  <times />  <pi />  <apply>  <power />  <cn type='integer'> 2 </cn>  <cn type='integer'> -1 </cn>  </apply>  </apply>  </apply>  </apply>  </apply>  </apply>  </apply>  </annotation-xml>  </semantics>  </math> 
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 | | Cell[BoxData[RowBox[List[RowBox[List["HoldPattern", "[", RowBox[List["ArcCosh", "[", FractionBox[RowBox[List["2", " ", "z_"]], RowBox[List[SuperscriptBox["z_", "2"], "+", "1"]]], "]"]], "]"]], "\[RuleDelayed]", RowBox[List[FractionBox[RowBox[List[SqrtBox[RowBox[List["-", SuperscriptBox[RowBox[List["(", RowBox[List["z", "-", "1"]], ")"]], "2"]]]], " ", SqrtBox[RowBox[List["z", "+", "1"]]], " ", SqrtBox[FractionBox["1", RowBox[List["z", "+", "1"]]]], " ", RowBox[List["(", RowBox[List[RowBox[List[RowBox[List["-", "2"]], " ", "\[ImaginaryI]", " ", RowBox[List["ArcTanh", "[", RowBox[List["\[ImaginaryI]", " ", "z"]], "]"]]]], "+", FractionBox[RowBox[List["3", " ", "\[Pi]"]], "2"]]], ")"]]]], RowBox[List["z", "-", "1"]]], "/;", RowBox[List[RowBox[List[RowBox[List["Abs", "[", "z", "]"]], ">", "1"]], "&&", RowBox[List["(", RowBox[List[RowBox[List[FractionBox["\[Pi]", "2"], "<", RowBox[List["Arg", "[", "z", "]"]], "\[LessEqual]", "\[Pi]"]], "||", RowBox[List[RowBox[List["-", "\[Pi]"]], "<", RowBox[List["Arg", "[", "z", "]"]], "\[LessEqual]", RowBox[List["-", FractionBox["\[Pi]", "2"]]]]]]], ")"]]]]]]]]]] | 
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 | | Date Added to functions.wolfram.com (modification date) | 
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