[CAS] find domain for function?

[Aries]

As for polynomials functions there is no problem, their domain is R.
For fractional functions 1/f(x) we can solve f(x)=0 and the roots are the ones to be excluded from R.
For irrational functions sqrt(f(x)), solving f(x)>=0 is enough.
In many cases in order to find the domain of a function we need to set a system:
y=sqrt(log(x^2-8*x+8)), solve({x^2-8*x+8>0,log(x^2-8*x+8)>=0}) and that's all !!!
Domain found !!!!!
Algebraically, not graphically B-) ^_^
Best,

Aries ;-)