But... sage: eq = sqrt((pi-5)^2) sage: eq.canonicalize_radical() pi - 5
And as you can read from the documentation """ Choose a canonical branch of the given expression. The square root, cube root, natural log, etc. functions are multi-valued. The "canonicalize_radical()" method will choose *one* of these values based on a heuristic. """ As Simon said, be careful if you start using canonicalize_radical since it does not preserve equality sage: eq = sqrt((pi-5)^2) sage: eq.numerical_approx() 1.85840734641021 sage: eq.canonicalize_radical().numerical_approx() -1.85840734641021 Vincent 2015-02-27 14:36 UTC+01:00, Simon King <simon.k...@uni-jena.de>: > Hi Paul, > > On 2015-02-27, Paul Royik <distantjob...@gmail.com> wrote: >> What is the way to consistently simplify square roots of squares? >> >> Examples: >> >> sqrt((x+1)^2) - > x+1 >> sqrt(cos(4*x)+1) -> sqrt(2)cos(2x) > > Simplification must not change the value of the expression. sqrt(x^2) is > certainly not equal to x. Even under the additional assumption that x is > real, you could only simplify it to abs(x) > > Best regards, > Simon > > > -- > You received this message because you are subscribed to the Google Groups > "sage-support" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-support+unsubscr...@googlegroups.com. > To post to this group, send email to sage-support@googlegroups.com. > Visit this group at http://groups.google.com/group/sage-support. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
