You are choosing between two texting plans. Plan A has a monthly fee of $15 with a charge of $0.05 per text. Plan B has a monthly fee of $5 with a charge of $0.07 per text. a. Express the monthly cost for plan A, f, as a function of the number of text messages in a month, x. b. Express the monthly cost for plan B, g, as a function of the number of text messages in a month, x. c. For how many text messages will the costs for the two plans be the same?

Calculus notes for week of 9/19/16 3.6 Derivatives as Rates of Change Velocity is measured as: V ave(t+∆t) or s(b) – s(a) ∆t b – a (Change in position over change in time.) S’’(t) = V’(t) = A(t) (From left to right: S=Position, V= Velocity, and A=Acceleration) Average and Marginal Cost Suppose C(x) gives the total cost to produce x units of a good cost. Sometimes,...