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István Zachar
István Zachar
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how How to extract expression from conditional expressionConditionalExpression

p1 := y /. {First[Solve[x^2 + y^2 + x == 1, y, Reals]]}

outputs:

{ConditionalExpression[-Sqrt[1 - x - x^2], 

{ConditionalExpression[-Sqrt[1 - x - x^2], 
  1/2 (-1 - Sqrt[5]) < x < 1/2 (-1 + Sqrt[5])]}

I want to get the -Sqrt[1 - x - x^2] out of therethe conditional expression and assign it to a variable. I don't care about the conditions, I'm aware of them and need the expression for use out of the Conditional ExpressionConditionalExpression. How How do I do that?

I tried list commands combinations (flattenFlatten, first.First, etc.) but they don't work with this.

  Am I just supposed to copy-paste?

how to extract expression from conditional expression

p1 := y /. {First[Solve[x^2 + y^2 + x == 1, y, Reals]]}

outputs:

{ConditionalExpression[-Sqrt[1 - x - x^2], 
  1/2 (-1 - Sqrt[5]) < x < 1/2 (-1 + Sqrt[5])]}

I want to get the -Sqrt[1 - x - x^2] out of there and assign it to a variable. I don't care about the conditions, I'm aware of them and need the expression for use out of the Conditional Expression. How do I do that?

I tried list commands combinations (flatten, first..) but they don't work with this.

  Am I just supposed to copy-paste?

How to extract expression from ConditionalExpression

p1 := y /. {First[Solve[x^2 + y^2 + x == 1, y, Reals]]}

{ConditionalExpression[-Sqrt[1 - x - x^2], 

   1/2 (-1 - Sqrt[5]) < x < 1/2 (-1 + Sqrt[5])]}

I want to get the -Sqrt[1 - x - x^2] out of the conditional expression and assign it to a variable. I don't care about the conditions, I'm aware of them and need the expression for use out of the ConditionalExpression. How do I do that?

I tried list commands combinations (Flatten, First, etc.) but they don't work with this. Am I just supposed to copy-paste?

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Edoz
Edoz
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how to extract expression from conditional expression

p1 := y /. {First[Solve[x^2 + y^2 + x == 1, y, Reals]]}

outputs:

{ConditionalExpression[-Sqrt[1 - x - x^2], 
  1/2 (-1 - Sqrt[5]) < x < 1/2 (-1 + Sqrt[5])]}

I want to get the -Sqrt[1 - x - x^2] out of there and assign it to a variable. I don't care about the conditions, I'm aware of them and need the expression for use out of the Conditional Expression. How do I do that?

I tried list commands combinations (flatten, first..) but they don't work with this.

Am I just supposed to copy-paste?