# Revision history [back]

### i doesn't belong to QQbar ? Why ?

I do not understand this :

sage: sqrt(1) in QQbar
True
sage: sqrt(-2) in QQbar
True
sage: sqrt(-1) in QQbar
False


Can someone explain ?

### i doesn't belong to QQbar ? Why ?

I do not understand this :

sage: sqrt(1) in QQbar
True
sage: sqrt(-2) in QQbar
True
sage: sqrt(-1) in QQbar
False


Can someone explain ?

Note that, however :

sage: [t[0] in QQbar for t in (x^2+1).roots(ring=QQbar)]
[True, True]

 3 retagged tmonteil 25173 ●29 ●178 ●468 http://wiki.sagemath.o...

### i doesn't belong to QQbar ? Why ?

I do not understand this :

sage: sqrt(1) in QQbar
True
sage: sqrt(-2) in QQbar
True
sage: sqrt(-1) in QQbar
False


Can someone explain ?

Note that, however :

sage: [t[0] in QQbar for t in (x^2+1).roots(ring=QQbar)]
[True, True]

 4 retagged tmonteil 25173 ●29 ●178 ●468 http://wiki.sagemath.o...

### i doesn't belong to QQbar ? Why ?

I do not understand this :

sage: sqrt(1) in QQbar
True
sage: sqrt(-2) in QQbar
True
sage: sqrt(-1) in QQbar
False


Can someone explain ?

Note that, however :

sage: [t[0] in QQbar for t in (x^2+1).roots(ring=QQbar)]
[True, True]