# Sage cannot simplify expressions with radical functions?

Sage cannot seem to simplify symbolic expressions containing radical functions, even if I specify the domain and use assumptions:

```
var('x', domain='positive')
assume(x>1)
bool(sqrt(x-1)>0) # True
bool(sqrt((x-1)^3)-(x-1)*sqrt(x-1)==0) #True
# not true even with x>1 assumption?
bool(sqrt(x^3-x^2)-x*sqrt(x-1)==0) #False
```

I know there is the `simplify_chain_real()`

function that can simplify `sqrt(x^3-x^2)`

to `sqrt(x-1)*x`

, but shouldn't the `bool()`

function force a simplification? And why the behavior is different (and correct) for `bool(sqrt((x-1)^3)-(x-1)*sqrt(x-1)==0)`

?

Thanks