.
Find the domain and range
f(x)= -x^2-10x
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The domain is (
, 
), the set of all real numbers.
The range is from to 
.
Find the maximum of f(x).
It is y-coordinate of its vertex.
To find it, you can complete the square:
= 
= 
= 
+ 
.
The maximum is at x = -5, and it is equal to 25.
Hence, the range is (, ).
