optimization

Question

The number y (in millions) of VCRs in use in the United States for the years 1990 through 2003 can be modeled by y=-0.17t^2+4.3t+60., where t=0 represents 1990

a. Using your graphing calculator to graph the model, give the year when the number of VCRs in use is the maximum.

b. Give the maximum number of VCRs in use.

c. Do you think it would be reasonable to use this model to estimate the number of VCRs in year 2010? Explain your answer.

Answer 1

I made the plot of the model in Excel and the results were as follows:

The year when the number of VCR is the maximum is 2013

The number of VCR is 87.17 million

No because the curve begins to descend towards Zero and then after 7 more years will give a wrong answer.