Question 460501
 domain of f(x)= x^2-9
All real numbers.
.
domain of f(x)=sqrt(x+2)
X[-2, infinity)
.
range of sqrt(x+2) 
Y[0, infinity)
.
range of x^2-4
minimum of x is -b/2a = 0/2 = 0
minimum of y when x=0 is 0-4=-4
range=Y[-4, infinity)
.
Ed