Answer:
1,300 items
Explanation:
Given cost function:

where x is the number of items produced per week.
The given cost function C(x) is a quadratic equation with a positive leading coefficient, which means its graph is a parabola that opens upwards.
In such cases, the vertex of the parabola represents the minimum point of the function. Therefore, to minimize the cost, we need to find the vertex of the function. The x-coordinate of the vertex is the number of items that should be produced per week to minimize cost.
In a quadratic equation of the form y = ax² + bx + c, the x-coordinate of the vertex can be found using the formula x = -b/2a.
For the given function C(x):
- a = 0.003
- b = -7.8
- c = 15000
Substitute the values of a and b into the formula to find the x-coordinate of the vertex:

Therefore, 1,300 items should be produced per week to minimize cost.