Let f(x)=x^2-23. Write the correct response.
a. For what values of x is f (x)=13?
b. Using an opposite, explain why f is an even function
c. Name the vertex of the parabola defined by function f
d. Determine the domain and range of function f
a 13 = x^2-23
36 = x^2
x = +6 and -6
b "Even Function. A function with a graph that is symmetric with respect to the y-axis. A function is even if and only if f(–x) = f(x)"
Let's try 6 and -6 (which we already found both equate to 13....so it is even)
c -b/2a is the x value of the vertex point 0/-2 = 0
to find y sub x=0 into the equation = -23 Vertex = (0,-23)
d Domain is all x (-inf , + inf)
range is all y >= -23 [-23, +inf)