Question 242346
1. Square root requires positive values. 
Division by abs. value of x requires values not equal to zero.
The domain is then positive values greater than zero. 
x=({{{0}}},{{{infinity}}})
The "(" implies 0 is not included in the set, compared to "[" which would include it. 
2. No restrictions on absolute value. 
Division by x requires values not equal to zero.
The domain is all values other than zero. 
x=({{{-infinity}}},{{{0}}})U({{{0}}},{{{infinity}}})