Consider the equation *(I*x^51+sum(x^k,k,0,50))==0* Try to solve it numerically using *solve([(I*x^51+sum(x^k,k,0,50))==0,x==x],x,solution_dict=True)* and you obtain 51 solutions of which 50 have modulus approximately 1 and the other is close to 1+I. Substituting back gives residuals of around at most 10^-6. That looks fine and Mathematica gives similar solutions. Now substitute x-1-I for x, so that one of the solutions should now be close to zero. Sage now gives solutions with real and imaginary parts both between -1 and +4, but none are particularly close to zero.The residuals now range up to 10^20. Mathematica gives completely different answers but which are also wrong, namely all 51 are approximately 1.
Any ideas? Tony Wickstead -- 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/groups/opt_out.
