SOLUTION: i really need help with this one. f(x)=2x^-12x-4 a)determine without graphing whether the function has a minimum or maximum value b)find minimum or maximum value and determine wh

Algebra ->  Rational-functions -> SOLUTION: i really need help with this one. f(x)=2x^-12x-4 a)determine without graphing whether the function has a minimum or maximum value b)find minimum or maximum value and determine wh      Log On


   

Question 394916: i really need help with this one. f(x)=2x^-12x-4
a)determine without graphing whether the function has a minimum or maximum value
b)find minimum or maximum value and determine where it occurs
c)identify the functions domain and range
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
I will assume the function to be f%28x%29+=+2x%5E2-12x-4.
The domain is R, the set of all real numbers. The graph is a parabola opening upward (a = 2 > 0) , and so the function has a minimum (corresponding to the vertex.)
.
The vertex is thus the point (3, -22). So the minimum occurs at x = 3, and the minimum value is -22.
The range of the function is [-22, infinity).