Find the critical points of the function. (enter your answers as a comma-separated list.) g(x) = 4 − x2

Please use "^" to denote exponentiation:  g(x) = 4 - x^2.

To find the critical point, differentiate g(x), set the result = to 0, and solve for x:

g '(x) = -2x = 0.  Then x = 0 is the only critical value in this case.

The graph of g(x) is a vertical parabola opening down, and the horizontal tangent line is y = 4.