The United States has been consuming iron ore at the rate of R(t) million metric tons per year at time t, where t is measured in years since 1980 (that is, t = 0 corresponds to the year 1980), and R(t) = 18.94e0.02t Find a formula T(t) for the total U.S. consumption of iron ore, in millions of metric tons, from 1980 until time t T(t) =

Respuesta :

Answer:

 T(t) = 947*(e^0.02t - 1)

Step-by-step explanation:

Given:

                                   R(t) = 18.94 e^0.02t

Find:

Find a formula T(t) for the total U.S. consumption of iron ore, in millions of metric tons, from 1980 until time t.

Solution:

- The rate of change:

                                   dT / dt = R(t)

                                   dT / dt = 18.94 e^0.02t

- Separate variables:

                                   dT = 18.94 e^0.02t .dt

- Integrate both sides:

                                   T = (18.94/0.02)*e^0.02t + C

                                   T = 947*e^0.02t + C

- Evaluate C where T = 0 @ t = 0:

                                    0 = 947*1 + C

                                    C = -947

- Hence,

                                   T(t) = 947*(e^0.02t - 1)

             

Using a integral, it is found that the formula for total U.S. consumption of iron ore, in t years after 1980, is:

[tex]T(t) = 947e^{0.02t} - 947[/tex]

The yearly consumption, in t years since 1980, is modeled by:

[tex]R(t) = 18.94e^{0.02t}[/tex]

The total is the integral of the yearly consumption, hence:

[tex]T(t) = \int_{0}^t R(t) dt[/tex]

[tex]T(t) = \int_{0}^t 18.94e^{0.02t} dt[/tex]

[tex]T(t) = 947e^{0.02t}|_{0}^{t}[/tex]

[tex]T(t) = 947e^{0.02t} - 947[/tex]

A similar problem is given at https://brainly.com/question/21439037