I need to know the range of the problem f(x) = 10 - x^2 for my precalculus test.
x^2 is always positive.
So -x^2 is always negative.
That means that 10 - x^2 is negative for large values of x.
10 - x^2 is only positive for x smaller than sqrt(10), and has its greatest positive value when x = 0.
That greatest value is f(0) = 10.
The range of the function then is from minus infinity to plus 10.
Range = (-ꝏ, 10]