Solve the problem.Given the revenue and cost functions R = 26x – 0.3×2 and , where x is the daily production, find the rate of change of profit with respect to time when 20 units are produced and the rate of change of production is 4 units per day.

Find the x-value of all points where the function has relative extrema. Find the value(s) of any relative extrema.f(x) = x2 + 2x – 3

Find all the critical numbers of the function.f(x) = x3 + x2 – 27x + 2

Solve the problem.Given the revenue and cost functions R = 26x – 0.3×2 and , where x is the daily production, find the rate of change of profit with respect to time when 20 units are produced and the rate of change of production is 4 units per day.

Find the open interval(s) where the function is changing as requested.Increasing; f(x) = x2 – 2x + 1

Find the derivative.y = (x-2 + x)-3

Solve the problem.A rectangular field is to be enclosed on four sides with a fence. Fencing costs $6 per foot for two opposite sides, and $5 per foot for the other two sides. Find the dimensions of the field of area 880 ft2 that would be the cheapest to enclose.

Give an appropriate answer.Letf(x) = 4 andg(x) = -5. Find[f(x) – g(x)].

Use the quotient rule to find the derivative.y = 

Give an appropriate answer.Letf(x) = -4 andg(x) = 1. Find[f(x) – g(x)].