How do I assign the solutions of an equation to separate variables?

Question

I'm a beginner to Mathematica. Here's my question.

I'd like to store the output(s) of a Solve command to variable(s) that can be manipulated later.

For example, I would like x1 and x2 to be the two solutions of x^2 - x - 1. I start with this

Clear[f, x]; f[x_] = x^2 - x - 1; solutions = Solve[f[x] == 0, x]

To be clear, I want x1 to have value

(1/2)(1 - Sqrt[5])

and NOT {x -> (1 - Sqrt[5])/2}

so that I could input

x1 + Sqrt[5]

and get output

(1/2)(1 - Sqrt[5])

How do I do this? Any help is much appreciated.

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See http://reference.wolfram.com/language/howto/UseRuleSolutions.html and http://support.wolfram.com/kb/12505. Related Q&A: (3175), (6669) — Michael E2, Jul 26 '15 at 19:47

score 1 · Answer 1 · answered Jul 26 '15 at 19:46

1

I would use

{x1, x2} = x /. solutions

answered Jul 26 '15 at 19:46

Szabolcs

1 Answers1