On Monday, January 13, 2014 4:32:10 PM UTC-8, Gregory Bard wrote: > > Hi everyone. I might be confused but I think I've found something not > quite right. > > The following code: > > ############################### > a(x) = x^2 - 5*x + 6 > b(x) = x^2 - 8*x + 15 > > f(x) = lcm( a(x), b(x) ) > > print f > > print f.rational_simplify() > ############################### > > produces the output > > x |--> (x^2 - 5*x + 6)*(x^2 - 8*x + 15)/(x - 3) > > x |--> x^3 - 10*x^2 + 31*x - 30 > > The latter is more my view of what f(x) should be. Am I wrong? > Should the lcm of two polynomials be a polynomial? > > In any case, I imagine the lcm is computed by multiplying a(x) > and b(x) together, and then dividing by their gcd. However, > shouldn't rational_simplify() be called on that quotient before > returning the solution? > > Thoughts? > ---Greg > > p.s. While I have everyone's attention, is there a > polynomial-long-division command in Sage? By polynomial long > division, I mean the rote algorithm taught in College Algebra, > not Groebner Bases. I searched for a while but didn't find one. > > That's fine, it is a rare task, but I thought I'd double check... > > Division with remainder is available in Maxima as the command divide. e.g. divide(a, x-4,x) returns the pair, x-1 and 2 for quotient and remainder. LCM is available in Maxima as lcm. It probably has the semantics you expect.
If you want a tableau displaying the steps in polynomial long division, or synthetic division (?) then Divide() won't satisfy your request. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/groups/opt_out.
