Problem with roots cmd
Publié : sam. sept. 22, 2018 1:58 pm
Hi, sometimes when x is assumed as an integer, xcas is restarted.
Test example
assume(x, integer);
roots(x^3 - 13/5*i*x^2 - 8*x^2 + 29/5*i*x + 81/5*x + 6*i - 18/5,x); => [[3,1]]
purge(x);
roots(x^3 - 13/5*i*x^2 - 8*x^2 + 29/5*i*x + 81/5*x + 6*i - 18/5,x); => [[3,1],[5+3*i,1],[(-2*i)/5,1]]
Another case
roots(a*x^2 + b*x + c)
f(x) := 5*x - 3; solve(f(y)=0)
Test example
assume(x, integer);
roots(x^3 - 13/5*i*x^2 - 8*x^2 + 29/5*i*x + 81/5*x + 6*i - 18/5,x); => [[3,1]]
purge(x);
roots(x^3 - 13/5*i*x^2 - 8*x^2 + 29/5*i*x + 81/5*x + 6*i - 18/5,x); => [[3,1],[5+3*i,1],[(-2*i)/5,1]]
Another case
roots(a*x^2 + b*x + c)
f(x) := 5*x - 3; solve(f(y)=0)