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Publié : **dim. oct. 10, 2021 9:04 pm**

Hi,
By solving the system in giac 1.7.0-25

sol:=solve([(2*x1^5+4*x1^3+2*x1*x2+2*x1)/(x1^2*x2+x2),x1^4+2*x1^2+x2^2-3],[x1,x2])

I get four solutions:

[[0,sqrt(3)],[0,-(sqrt(3))],[sqrt((sqrt(2*(sqrt(17)-1))-2)/2),(-(sqrt(17))+1)/2],[-(sqrt((sqrt(2*(sqrt(17)-1))-2)/2)),(-(sqrt(17))+1)/2]]

However, the second expression in the system does not vanish for the fourth solution: the command

normal(subs(x1^4+2*x1^2+x2^2-3,[x1,x2],sol[3]))

yields

-(sqrt(17))

Publié : **mar. oct. 12, 2021 9:40 am**

Normal is wrong (evalf returns approx 0), it's probably the same bug as your other report, I will investigate.

Publié : **mar. oct. 12, 2021 7:55 pm**

Everything is fine in Xcas 1.7.0-35 in Windows.

solve returning infeasible solution