Find the maximum profit and the number of units that must be produced and sold in order to yield the maximum profit. Assume that revenue, Upper R (x ), and cost, Upper C (x ), are in thousands of dollars, and x is in thousands of units. Upper R (x )equals9 x minus 2 x squared, Upper C (x )equalsx cubed minus 3 x squared plus 4 x plus 1

-1.39

Step-by-step explanation:

Revenue and cost as a function of units sold are and  respectively.

we are have to know for which value or input units are these functions at maximum which translates to for how many units is the revenue maximum and for how many same units is our cost minimum.

3< x< 5

step-by-step explanation:

|x - 4| < 1

there are two solutions, one positive and one negative.   remember to flip the inequality when taking the negative solution

x-4 < 1       x-4 > -1

add 4 to each side

x-4+4 < 1+4       x-4+4 > -1+4

x< 5                 x> 3

3< x< 5

so, converting firstly the mixed fractions to improper fractions and then "adding".