(x+e^-x)/sqrt(|x|+x) has a limited domain because of the square root in the denominator. Also x cannot be zero because that would cause division by zero which is disallowed. When x<-x, i.e., when x<0, division by zero would also occur because |x|+x becomes -x+x=0. So the domain for x is x>0, for which numerator and denominator are both defined (denominator becomes sqrt(2x)).