A manufacturer produces items at a cost of Cx 2x2 16x 40 d
A manufacturer produces items at a cost of C(x) = 2x^2 -16x + 40 dollars. The items are later sold for a reasonable profit. Rewrite the function in the form C(x) = a(x - h)^2 +k. What transformations would have to be applied to f(x) = x^2 for it to become C(x) above? Find the y-intercept and interpret what it means in the context of the problem. Find any x-intercepts and interpret what they mean in the context of the problem. Find the vertex and interpret the coordinates in the context of the problem.(vertex is max/min)
Solution
a)C(x) = 2x^2 -16x +40
C(x) = 2(x^2 - 8x +20)
= 2(x -4)^2 +16
Comparing it with C(x) = a(x-h)^2 +k
b) Parent function f(x) = x^2
Transformations applied:
i) Horizontal shift of 4 units to right (x-4)^2
ii) Vertical scaling of 2 units 2(x-4)^2
iii) Vertical shift of 16 units : 2(x-4)^2 +16
c) y intercept when x=0
C(0) = 2*4^2 +16 = 48
This is the fixed cost of manfucaturing
d) x intercept : when C(x) =0
0= 2x^2 -16x +40
x^2 - 8x +20 =0
solve for x : x = imaginary roots
So,no x intercepts exist
e) C(x) = 2(x-4)^2 +16
Vertex : ( 4 , 16)
Minimum value of C(x) is at vertex
