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 | | http://functions.wolfram.com/01.11.17.0002.01 | 
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 | | (Sec[Subscript[z, 1]]^2 Sec[Subscript[z, 2]]^2 - Sec[Subscript[z, 1]]^2 - 
    Sec[Subscript[z, 2]]^2) Sec[Subscript[z, 1] + Subscript[z, 2]]^2 + 
  2 Sec[Subscript[z, 1]] Sec[Subscript[z, 2]] 
   Sec[Subscript[z, 1] + Subscript[z, 2]] - Sec[Subscript[z, 1]]^2 
   Sec[Subscript[z, 2]]^2 == 0 | 
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 | | Cell[BoxData[RowBox[List[RowBox[List[RowBox[List[RowBox[List["(", RowBox[List[RowBox[List[SuperscriptBox[RowBox[List["Sec", "[", SubscriptBox["z", "1"], "]"]], "2"], " ", SuperscriptBox[RowBox[List["Sec", "[", SubscriptBox["z", "2"], "]"]], "2"]]], "-", SuperscriptBox[RowBox[List["Sec", "[", SubscriptBox["z", "1"], "]"]], "2"], "-", SuperscriptBox[RowBox[List["Sec", "[", SubscriptBox["z", "2"], "]"]], "2"]]], ")"]], " ", SuperscriptBox[RowBox[List["Sec", "[", RowBox[List[SubscriptBox["z", "1"], "+", SubscriptBox["z", "2"]]], "]"]], "2"]]], "+", RowBox[List["2", " ", RowBox[List["Sec", "[", SubscriptBox["z", "1"], "]"]], " ", RowBox[List["Sec", "[", SubscriptBox["z", "2"], "]"]], " ", RowBox[List["Sec", "[", RowBox[List[SubscriptBox["z", "1"], "+", SubscriptBox["z", "2"]]], "]"]]]], "-", RowBox[List[SuperscriptBox[RowBox[List["Sec", "[", SubscriptBox["z", "1"], "]"]], "2"], " ", SuperscriptBox[RowBox[List["Sec", "[", SubscriptBox["z", "2"], "]"]], "2"]]]]], "\[Equal]", "0"]]]] | 
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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>  <mrow>  <mo> - </mo>  <mrow>  <msup>  <mi> sec </mi>  <mn> 2 </mn>  </msup>  <mo> ( </mo>  <msub>  <mi> z </mi>  <mn> 1 </mn>  </msub>  <mo> ) </mo>  </mrow>  </mrow>  <mo> ⁢ </mo>  <mrow>  <msup>  <mi> sec </mi>  <mn> 2 </mn>  </msup>  <mo> ( </mo>  <msub>  <mi> z </mi>  <mn> 2 </mn>  </msub>  <mo> ) </mo>  </mrow>  </mrow>  <mo> + </mo>  <mrow>  <mn> 2 </mn>  <mo> ⁢ </mo>  <mrow>  <mi> sec </mi>  <mo> ⁡ </mo>  <mo> ( </mo>  <msub>  <mi> z </mi>  <mn> 1 </mn>  </msub>  <mo> ) </mo>  </mrow>  <mo> ⁢ </mo>  <mrow>  <mi> sec </mi>  <mo> ⁡ </mo>  <mo> ( </mo>  <mrow>  <msub>  <mi> z </mi>  <mn> 1 </mn>  </msub>  <mo> + </mo>  <msub>  <mi> z </mi>  <mn> 2 </mn>  </msub>  </mrow>  <mo> ) </mo>  </mrow>  <mo> ⁢ </mo>  <mrow>  <mi> sec </mi>  <mo> ⁡ </mo>  <mo> ( </mo>  <msub>  <mi> z </mi>  <mn> 2 </mn>  </msub>  <mo> ) </mo>  </mrow>  </mrow>  <mo> + </mo>  <mrow>  <mrow>  <mo> ( </mo>  <mrow>  <mrow>  <mrow>  <msup>  <mi> sec </mi>  <mn> 2 </mn>  </msup>  <mo> ( </mo>  <msub>  <mi> z </mi>  <mn> 2 </mn>  </msub>  <mo> ) </mo>  </mrow>  <mo> ⁢ </mo>  <mrow>  <msup>  <mi> sec </mi>  <mn> 2 </mn>  </msup>  <mo> ( </mo>  <msub>  <mi> z </mi>  <mn> 1 </mn>  </msub>  <mo> ) </mo>  </mrow>  </mrow>  <mo> - </mo>  <mrow>  <msup>  <mi> sec </mi>  <mn> 2 </mn>  </msup>  <mo> ( </mo>  <msub>  <mi> z </mi>  <mn> 1 </mn>  </msub>  <mo> ) </mo>  </mrow>  <mo> - </mo>  <mrow>  <msup>  <mi> sec </mi>  <mn> 2 </mn>  </msup>  <mo> ( </mo>  <msub>  <mi> z </mi>  <mn> 2 </mn>  </msub>  <mo> ) </mo>  </mrow>  </mrow>  <mo> ) </mo>  </mrow>  <mo> ⁢ </mo>  <mrow>  <msup>  <mi> sec </mi>  <mn> 2 </mn>  </msup>  <mo> ( </mo>  <mrow>  <msub>  <mi> z </mi>  <mn> 1 </mn>  </msub>  <mo> + </mo>  <msub>  <mi> z </mi>  <mn> 2 </mn>  </msub>  </mrow>  <mo> ) </mo>  </mrow>  </mrow>  </mrow>  <mo> ⩵ </mo>  <mn> 0 </mn>  </mrow>  <annotation-xml encoding='MathML-Content'>  <apply>  <eq />  <apply>  <plus />  <apply>  <times />  <apply>  <times />  <cn type='integer'> -1 </cn>  <apply>  <power />  <apply>  <sec />  <apply>  <ci> Subscript </ci>  <ci> z </ci>  <cn type='integer'> 1 </cn>  </apply>  </apply>  <cn type='integer'> 2 </cn>  </apply>  </apply>  <apply>  <power />  <apply>  <sec />  <apply>  <ci> Subscript </ci>  <ci> z </ci>  <cn type='integer'> 2 </cn>  </apply>  </apply>  <cn type='integer'> 2 </cn>  </apply>  </apply>  <apply>  <times />  <cn type='integer'> 2 </cn>  <apply>  <sec />  <apply>  <ci> Subscript </ci>  <ci> z </ci>  <cn type='integer'> 1 </cn>  </apply>  </apply>  <apply>  <sec />  <apply>  <plus />  <apply>  <ci> Subscript </ci>  <ci> z </ci>  <cn type='integer'> 1 </cn>  </apply>  <apply>  <ci> Subscript </ci>  <ci> z </ci>  <cn type='integer'> 2 </cn>  </apply>  </apply>  </apply>  <apply>  <sec />  <apply>  <ci> Subscript </ci>  <ci> z </ci>  <cn type='integer'> 2 </cn>  </apply>  </apply>  </apply>  <apply>  <times />  <apply>  <plus />  <apply>  <times />  <apply>  <power />  <apply>  <sec />  <apply>  <ci> Subscript </ci>  <ci> z </ci>  <cn type='integer'> 2 </cn>  </apply>  </apply>  <cn type='integer'> 2 </cn>  </apply>  <apply>  <power />  <apply>  <sec />  <apply>  <ci> Subscript </ci>  <ci> z </ci>  <cn type='integer'> 1 </cn>  </apply>  </apply>  <cn type='integer'> 2 </cn>  </apply>  </apply>  <apply>  <times />  <cn type='integer'> -1 </cn>  <apply>  <power />  <apply>  <sec />  <apply>  <ci> Subscript </ci>  <ci> z </ci>  <cn type='integer'> 1 </cn>  </apply>  </apply>  <cn type='integer'> 2 </cn>  </apply>  </apply>  <apply>  <times />  <cn type='integer'> -1 </cn>  <apply>  <power />  <apply>  <sec />  <apply>  <ci> Subscript </ci>  <ci> z </ci>  <cn type='integer'> 2 </cn>  </apply>  </apply>  <cn type='integer'> 2 </cn>  </apply>  </apply>  </apply>  <apply>  <power />  <apply>  <sec />  <apply>  <plus />  <apply>  <ci> Subscript </ci>  <ci> z </ci>  <cn type='integer'> 1 </cn>  </apply>  <apply>  <ci> Subscript </ci>  <ci> z </ci>  <cn type='integer'> 2 </cn>  </apply>  </apply>  </apply>  <cn type='integer'> 2 </cn>  </apply>  </apply>  </apply>  <cn type='integer'> 0 </cn>  </apply>  </annotation-xml>  </semantics>  </math> 
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 | | Cell[BoxData[RowBox[List[RowBox[List["HoldPattern", "[", RowBox[List[RowBox[List[RowBox[List["(", RowBox[List[RowBox[List[SuperscriptBox[RowBox[List["Sec", "[", SubscriptBox["z_", "1"], "]"]], "2"], " ", SuperscriptBox[RowBox[List["Sec", "[", SubscriptBox["z_", "2"], "]"]], "2"]]], "-", SuperscriptBox[RowBox[List["Sec", "[", SubscriptBox["z_", "1"], "]"]], "2"], "-", SuperscriptBox[RowBox[List["Sec", "[", SubscriptBox["z_", "2"], "]"]], "2"]]], ")"]], " ", SuperscriptBox[RowBox[List["Sec", "[", RowBox[List[SubscriptBox["z_", "1"], "+", SubscriptBox["z_", "2"]]], "]"]], "2"]]], "+", RowBox[List["2", " ", RowBox[List["Sec", "[", SubscriptBox["z_", "1"], "]"]], " ", RowBox[List["Sec", "[", SubscriptBox["z_", "2"], "]"]], " ", RowBox[List["Sec", "[", RowBox[List[SubscriptBox["z_", "1"], "+", SubscriptBox["z_", "2"]]], "]"]]]], "-", RowBox[List[SuperscriptBox[RowBox[List["Sec", "[", SubscriptBox["z_", "1"], "]"]], "2"], " ", SuperscriptBox[RowBox[List["Sec", "[", SubscriptBox["z_", "2"], "]"]], "2"]]]]], "]"]], "\[RuleDelayed]", "0"]]]] | 
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 | | Date Added to functions.wolfram.com (modification date) | 
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