Suppose that the cost function for a commodity is

$C(x)=80+x^2$ dollars.

$($a$)$ Find the marginal cost at $x=3$ units.

$\frac{?}{\text{b}\text{a}\text{r}}(MC)(3)=$

Tell what this predicts about the cost of producing $1$ additional unit.

The cost to produce the $4$ the unit is predicted to be $

$($b$)$ Calculate $C(4)-C(3)$ to find the actual cost of producing $1$ additional unit. $

Need Help?